Elric
Well-Known Member
Folks, while I like electrons for cut n paste, I much rather like reading a printed book. There might be a 2013 version available, but I have no idea on how well it has been reprinted. It might be an ebook?
Whatever. This extract comes from a version on the Internet Archive. When I drop this extract on a page, I will insert the images, which are well connected to the text...
v/r,
Elric
Handloader’s Manual - A Treatise on Modem Cartridge Components and their Assembly by the Individual Shooter into accurate Ammunition to best suit his various purposes
By Earl Naramore, Major, Ordnance Department Reserve, The Army of the United States
Sketches by LT. COL. Julian S. Hatcher
Small Arms Technical Publishing Co, Plantersville, South Carolina U. S. A. Sept 1937
Internet Archive, eBooks and Texts
https://ia800205.us.archive.org/1/i...1943/Handloaders_Manual_Naramore1943_text.pdf
Part II, Ammunition Assembly, Chapter 6, pages 183-201
THE CASTING OF BULLETS.
If all bullet moulds were the pink of perfection and if all bullet alloys flowed smoothly and alike and were the same temperature, the casting of bullets would be a very simple matter. It would only be necessary to melt the bullet metal, pour it into the mould and dump out a perfect bullet. While bullet moulds, as they come from the manufacturer today, cannot be considered as faulty and are very well made, each mould manufactured has its peculiarities and individualities. Different alloys of bullet metals do not all flow alike and cannot be used at a uniform temperature. Therefore, there is a little trick to casting good bullets that can only be learned by experience. While it will be possible to set down here certain principles, no amount of copy or directions can ever take the place of a few hours actual experience in casting bullets.
The materials necessary for casting good bullets are: a bullet mould; a dipper or ladle, preferably one made especially for the purpose as supplied by many of the reloading tool manufacturers and having a tubular spout, and a melting pot. A stout stick of wood about ten or twelve inches long is necessary for striking the sprue cutter; some wax or sal ammoniac for fluxing the bullet metal; a soft pad to drop the bullets on; an old box for the dross or oxidized metal that must be skimmed from the pot from time to time; and a source of heat for melting the bullet metal.
Source of Heat. The old-fashioned kitchen stove is sometimes criticized because of inability to control the heat accurately but this criticism is not justified because it is possible to control the heat of a coal fire by opening the drafts to increase the heat, or by checking the fire, or even by tipping the stove lids to decrease the heat and once the proper temperature of metal is obtained the even heat of a coal fire is very satisfactory. Of course, a gas or gasoline stove is more readily controlled and a little more convenient but is not a necessity.
Electric heating units are not as desirable as a gas flame as a general rule, for sometimes in casting bullets and in the preparation of metals and bullet alloys, an excessive amount of heat is necessary and electrical units are usually a little deficient in the heat that they produce. The ordinary electric stove is worthless, because the pot must set on top of the heating element so that only the bottom of the pot is heated while the greater area of the sides is cooled by the circulation of air. The small electrical bullet casting units are satisfactory in general but arc not adequate for preparing bullet alloys and when they arc used the bullet metal should be mixed and prepared over a hotter fire and then cast into small blocks of a convenient size for use in these small elements. A suitable' mould for the purpose can be made from a square box filled with damp sand pressed down firmly and with depressions made in the sand with the end of a broom handle. It should be borne in mind, however, that none of these electrical bullet casters have sufficient clearance beneath them to accommodate the conventional type of hollow-point bullet mould although they work quite nicely with all other types.
The principal objection to these electric bullet casters is that the metal is always drawn from the bottom of the pot. They are all made in the form of a small ladle or pot with a spout in the bottom. This little pot is surrounded by an electric heating element and is raised –up on a support so that the mould can be inserted beneath them with the pouring hole placed against the end of the spout. The spout is closed by a plunger passing down through the metal and the plunger is raised by means of a lever to permit the molten metal to flow out into the mould. To keep the alloy uniform, the metal must be fluxed and stirred frequently and with such a small amount of metal this cools the melt considerably. If the metal is not stirred frequently the lighter metals will rise towards the surface and a lead-rich mixture will be drawn from the bottom of the pot. They are, however, mostly satisfactory and are very handy for casting bullets, but like every other piece of reloading equipment they must be used with due consideration to the results that arc to be accomplished.
The ordinary melting pots and pouring ladles, while perhaps less convenient, will nevertheless, be best to use providing the source of heat is adequate, but here again they must be used properly. The larger volume of metal in the conventional melting pot can be kept at a more uniform temperature than in the diminutive electrical units and can be fluxed frequently without reducing the temperature of the melt below a satisfactory working point. But any advantage of the old fashioned lead pot is offset if the reloader continually dips metal from the surface of the pot, as is so often the case. Go to the bottom of your pot to fill your ladle as the movement of the ladle through the melt will help materially in keeping the metals thoroughly mixed.
Melting Pots. The lead pot should hold at least five pounds of bullet metal and preferably ten, as where the volume of metal is large a more uniform temperature can be maintained. This also permits the addition of new metal from time to time, without lowering the temperature of the metal below a set working point. Suitable lead pots can be obtained from any of the reloading tool manufacturers at small expense, while larger ones may be obtained from any plumbing supply house.
Pad for Hot Bullets. A pad must be provided on which to drop the bullets from the mould. The hot bullets are quite soft and are easily damaged and must not be allowed to strike a hard surface or to strike against each other. A piece of old blanket folded a few times is excellent but if a good blanket is used it should be covered with an old piece of cloth to prevent soil and scorch. If you have a work shop or arc situated so that you can have a few extra gadgets around without getting too many blessings from the family, a good bullet catcher can be made by stretching a piece of canton flannel, or any other soft cloth of good strength, across the top of a wooden box and tacking it in place around the edges. Bullets dropped on this will roll toward the center gently and when the accumulation of bullets becomes too heavy they can be removed carefully with a tablespoon.
Flux. Any kind of wax suitable for making bullet lubricant, powdered sal ammoniac or rosin make good materials for fluxing bullet metal. The waxes have a slight advantage in that the smoke produced can be ignited and burned; but you must resign yourself to some more or less unpleasant odors if you intend to cast your own bullets. Bullet alloys arc mixtures of lead and tin, lead and antimony, or all three of these metals. As the lead is the heavier of the three there is a tendency for the lighter metal to rise to the surface of the pot. The heat will also cause the metals to oxidize on the surface and these oxides form a scum on top of the metal that must be removed from time to time. The tin and antimony serve as hardening agents and they must not be skimmed off as this will change the hardness of the bullets. Fluxing the alloy will release the metals and leave the oxides in the form of black powder floating on top of the pot, which can be easily skimmed off with a bullet ladle leaving the alloy clean and bright. Experience will show the proper amount of fluxing material to use but the pot should never be skimmed without first fluxing the metal.
To do this, drop a piece of wax or a small amount of rosin or sal ammoniac into the pot and stir the metal rapidly. If wax is used, the gasses given off may ignite from the heat of the metal or can usually be ignited with a match, thus decreasing the amount of smoke and annoyance. The stirring will have a tendency to cool the mixture slightly and where the nature of the mould requires the use of a very hot bullet metal it is well to increase the flame under the pot, where this is possible, when fluxing. It is desirable to have a tin box at hand in which to drop the dross or oxides skimmed off but, as a matter of fact, any small box of wood or tin will serve.
Bullet Casting Procedure.
Now that we have all the materials at hand they should be arranged conveniently and the pot containing the bullet metal put over the fire to melt. If gas is used it should be turned up full till the metal is completely melted, after which the heat can be reduced as desired. The mould may be rested on the stove or placed close to the flame so as to heat up the block, but should not be allowed to get hot enough to burn any oil or grease that may be in the cavity.
When the metal is melted, put the ladle into it and allow it to heat. Then dip up some metal in the ladle, place the spout in a horizontal position against the pouring hole in the sprue cutter and turn both mould and dipper to a vertical position. Hold them in this position for a second or two. Remove the ladle, leaving some metal in the sprue hole. When the mould and metal are at the right temperature it will require a second or two for this excess metal to solidify but when first starting, the metal may solidify almost instantly due to the mould being too cold. The first bullets are apt to be misshapen affairs for the same reason. If the bullet metal is not hot enough it will solidify before completely filling the mould cavity. On the other hand, if the mould is too cold it will chill the metal before it has time to fill the cavity. When the mould and bullet metal are at the proper temperature it will require a second or two for the excess metal in the sprue hole to solidify after the ladle is removed. When the mould and metal are at such a temperature and the bullets do not fill out completely, it is usually due to mould blocks that fit too tightly together and do not permit the air to escape from some part of the cavity.
When the sprue has solidified the sprue cutter should be struck squarely with the stick and swung to one side, after which the mould may be opened over the pad, allowing the bullet to drop out. If the bullet does not drop out of its own accord, rap the side of the mould joint slightly with the stick of wood to jar the bullet out. Never stride a mould with a hammer or other metal object.
If the first bullets are not perfect, continue to cast them; they will get better and better as the mould warms up and you will shortly get perfect ones. As long as any oil or grease remains in the mould cavity the bullets will not fill up or they will be covered with small pits from the tiny gas bubbles formed when the hot metal comes into contact with the oil.
Breaking in a New Mould.
Most mould blocks arc made of malleable or alloy iron and come already blued or oxidized, so require no breaking in. If a mould cavity is bright it will not cast good bullets until the surface of the metal becomes oxidized. The ordinary procedure in such a case is to use the mould until the heat transmitted by the bullet metal accomplishes the desired result. This is often a long and tedious process and the job can be greatly hastened by placing the mould blocks on the top of a hot stove or by holding them near a gas flame until the cavity turns to a dark straw or blue. Before attempting to blue a mould cavity the mould should be washed in gasoline or carbon tetrachloride to remove all the oil, as the slushing oil used as a protection against rusting may carbonize and bum onto the mould. This will make blotchy bullets but the offending
carbon can usually be removed by rubbing with a soft cloth over the end of a wooden stick. It is a good plan to wash out any new mould, or any mould that has been oiled, before attempting to cast bullets with it. But if gasolene is used it should be outside of any room where there is an open flame. Gasolene is far more dangerous stuff than any kind of powder and the fumes carried to a flame by air currents have been responsible for many bad fires and fatal explosions.
Block Alignment. Contrary to popular belief a bullet mould is a precision implement and it must be used with reasonable care if it is to give long and satisfactory service. We all like to cast bullets with as much dispatch as possible but a little care in opening and closing the mould will not slow up the casting of good bullets to any appreciable extent and it will prolong the life of the bullet mould.
Most of the bullet moulds made today arc of the so called loose block type. The essential parts of one of these moulds arc shown in the illustration on Plate XIV. Each half of the mould block contains half of the mould cavity. Tins cavity is cut with a special reamer called a cherry which is made the exact shape of the bullet and no change can be made in the shape of the standard bullets, for which the manufacturers cut moulds, without making a new cherry which is an expensive job. However, some manufacturers will cut moulds for bullets that are longer or shorter than the standard, where the design of the cherry will permit.
The fit of the dowel pins on one block into the holes in the other block governs the alignment of the two halves of the cavity. When used properly there is very little wear on the holes or the pins but if the mould is yanked open and slammed shut, the holes will become burred at the edges and enlarged, which will throw the two halves of the block out of alignment and make it impossible to get perfect bullets from the mould. This looseness in the two halves of the block is known as “shuck” and can usually only be eliminated by returning the mould to the factory, having the holes reamed out larger and new dowel pins fitted.
Sprue Cutter Adjustment. The “sprue” cutter is a flat steel plate attached to the top of the mould block by a screw. The under surface of this plate fits closely against the flat top surface of the mould and forms the flat base of the bullet. The sprue cutter has a beveled hole in it, the bevel coming to a knife edge at the under side of the plate. This hole is the orifice through which the molten metal is poured into the mould and it is positioned approximately over the center of the cavity by a stop pin. The bevel of the pouring hole accommodates the dipper or the spout of the ladle, and the edge cuts off the “sprue” or overflow of metal after it solidifies.
The tension on the pivot screw of the sprue cutter should be sufficient to hold the cutter in firm aligning contact with the top of the block and if this screw becomes loose, metal is apt to flow in between the surface of the block and the bottom of the sprue cutter, forming a fin on the base of the bullet. If such a fin forms with the pivot screw reasonably tight, it is an indication that the sprue cutter is sprung and directions for attempting to overcome this condition are given elsewhere in this book. The stick of wood referred to above is necessary for striking the sprue cutter to cut off the sprue. Its size and shape are not important and any stick handy to use is all that is needed. A piece of old broom handle is excellent. Neither the sprue cutter nor any part of the mould should ever be struck with a metal object.
Corrosion of Moulds. Next to the individual who uses a bullet mould with more brawn than brains, the worst enemy of moulds is rust. Their oxidized film resists rust but will not prevent it. If you use your moulds frequently they can be put away with the last bullet left in them without opening the mould; that is, you can pour the mould full and leave it that way. This will exclude atmospheric moisture fairly well for a reasonable period of time under ordinary conditions but will not serve well where the humidity is high. When moulds are not to be used for a considerable period of time they should be oiled or greased. The grease or oil should be wiped off before using the mould again or, better still, washed off as already suggested.
CASTING TROUBLES AND THEIR REMEDIES.
Failure of Bullets to Drop From the Mould.
If the mould requires only slight jarring to make the bullets drop out, the condition can be ignored as a slight amount of “sticking” is unavoidable. The bullet usually persists in sticking in one certain half of the mould. Some operators tap the inside edge of that block with their stick—this is pretty apt to spring that half or cause it to warp open in time. Others tap the end of the handle in which half the bullet is stuck—this is apt to split that handle in time, but it can readily be replaced.
If one has to resort to pounding to get the bullets out there is something wrong and the mould will probably have to be returned to the manufacturer to have the defect remedied. The slightest damage to the sharp edges of the mould cavity will form a burr that will hold the bullets in and only an experienced mechanic can remove such a burr without damage to the mould. The average individual should not tamper with mould cavities in any way. Any manufacturer will correct a new mould that is at fault without charge, so it seems foolish to take a chance on ruining a four or five dollar mould.
Failure of Bullets to Fill Out. This is usually due to the mould, the metal or both being too cold. If the mould is too cold the metal will solidify before it has time to flow into all the comers. The net result will be the same if the metal is not hot enough. Sometimes mould blocks fit so closely together that the air cannot escape and with such a mould it is impossible to get good bullets unless the mould is “vented/’ Venting is done with a fine three-cornered file, with which shallow grooves are filed across the inside face of the mould blocks in such a way that the air may escape from the points where the bullet does not fill out properly. If the vents are filed too deep
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the bullet metal may flow into them when the mould and metal are very hot, but this does no harm as the projecting slivers will be sheared off when the bullet is sized. Venting can be done by anyone who is handy with a file but the file may slip and there is a good possibility that the file will burr the edge of the cavity. A vented mould is shown on this page which will serve better than a description of how the job is done. But remember—if a new mould does not cast good bullets the manufacturer will either vent it for you or replace it .
Bullets Out of Round. Due to shrinkage of some alloys when they cool, and to small manufacturing tolerances in the moulds, bullets may be a thousandth of an inch or so out of round as they come from the mould. They are purposely cast a little over size to permit truing them up in a sizing die of the correct diameter. If the variation in diameter is greater than two or three thousandths of an inch it may be due to a faulty mould, burred or enlarged dowel pin holes or to the presence of specks of lead on the inside faces of the mould blocks. Sometimes when dropping a defective bullet from the mould into the melting pot, lead will splash upward and small drops get caught between the mould blocks. These flatten when the mould is closed but hold the blocks apart enough to cause the bullets to be out of round. Such lead flakes are easily removed with a sharp knife.
Fins on Bullets. Mould blocks do not fit together properly or sprue cutter is not flat against top of mould blocks. If sprue cutter is loose tighten the pivot screw. If the sprue cutter is bent, remove it and try to straighten it with a light hammer. Then file the under surface flat, put it back on the mould and try it. If you cannot correct the difficulty in this way you will have to get a new sprue cutter. Burrs or raised metal around the dowel pin holes can be detected with a straight edge, they are easily removed with a flat file, hut care should be taken not to file across any part of the mould cavity.
Failure of Two Halves of the Mould Cavity to Coincide. The dowel pin holes are enlarged and the mould will have to be returned to the factory.
Frosted Bullets. When bullet metal cools it shows under the microscope as a crystalline formation. The size of the crystals depends upon the rate of cooling. If the metal cools quickly the crystals are small; if it cools slowly they are large. Bullets that solidify quickly in the mould will, therefore, usually have a bright shiny appearance but where the mould and the bullet metal are very hot and the metal cools slowly, the crystals will be so large that the bullet will have a frosted appearance. This difference in crystal size does no harm and has no affect on the performance of the bullet. If the mould and metal are allowed to cool down a little it will disappear but it must be borne in mind that some bullets with narrow bands, and especially bullets with hollow points and hollow bases, must oftentimes be cast with somewhat hotter metal than normal.
Folds and Seams. Either the mould or the metal is too cool.
Lead Smears On Top Surface of Mould Blocks. Usually caused by striking off the sprue when the mould
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is very hot and before the metal solidifies. This lead can usually be removed with a sharp knife when the mould is cold. It can also be removed with mercury. Be careful not to damage the edge of the cavity when you go to scraping around it with a sharp knife.
Elliptical or Lop-sided Bases. Generally confined to very soft bullets and caused by the base of the bullet being forced to one side when the sprue cutter is struck. See that the cutting edge of the cutter is sharp. It can be sharpened with a counter-sink turned with the fingers. If a soft alloy is used this defect can be reduced by closing the sprue cutter just far enough to allow the metal to be poured.
Hollows In Base of Bullet. These occur in bullets that are cast with a very hot mould and metal. The more slowly a bullet cools the coarser the grain structure will be and the more chance of the metal breaking off at the sprue. This leaves little crystalized depressions in the bullet bases. They do no harm other than to slightly reduce the weights of the bullets and only affect the accuracy to the extent that the weight of the bullet affects it.
Manufacture of Bullet Moulds.
Bullet moulds are ordinarily made from blocks of malleable iron. These blocks are machined to the proper shape and size and the interior surfaces carefully ground so that they will fit perfectly together. The two halves of the mould are then clamped together and arc drilled through at the proper points for the dowel pins and the corresponding holes in which the dowels are to fit. This insures perfect alignment of the two halves of the mould. A hole is then drilled in such a way that half of it is in each half of the mould block. After this the two halves of the block are brought together against a revolving cherry which is a special form of reamer that cuts a cavity the exact shape of the bullet. This sounds like a simple process and so it is to tell it on paper, but the operation is one calling for special skill and experience.
In the first place, a cherry is one of the most difficult reamers to make and frequently a lot of “fussing” is necessary before a new one will cut right. In making a cherry the stock is turned and ground to the shape of the bullet and to a size that will cut a cavity of the proper size. Ordinarily a cherry will not cut a cavity quite as large as itself unless allowed to run for an excessive length of time, and allowance must be made for this as well as for a possible shrinkage of the bullet alloy used. After the cherry is shaped the grooves must be milled in it longitudinally after which the real hard work begins for the tool maker. Merely cutting the grooves in the cherry will not leave it in condition so that it will cut, the ridges must be backed off before the cherry will cut, as the cutting edges or faces must always be the widest parts of the projections. This “backing off* is all careful hand work and the amount that the edges axe backed off depends upon the kind of metal the cherry is to be used on. For example, a cherry made for cutting cavities in malleable iron would not be satisfactory for use in steel or bronze and sometimes a cherry must be worked over several times before it will cut smoothly and without chattering. Even if the clearance is correct a cherry will chatter at times. If this happens when the cavity is nearly finished, both faces of the blocks must be reground and the cavity recut or the blocks may be cherried out for a larger caliber of bullet.
The older type bullet moulds had no detachable blocks, each half of the block being integral with one of the handles. The oldest ones had no dowel pins, but they were in general satisfactory. The objection to this type of mould was largely a manufacturing one for it was necessary to carefully fit the mould blocks before they were cherried and if anything went wrong with the cherrying the entire mould had to be scrapped. Furthermore, there was a tendency for the castings to warp under the influence of heat, throwing the two halves of the mould out of alignment. However, in spite of this many of these old moulds, including those that have no dowel pins, are still in satisfactory condition after years of use.
With detachable blocks, cherrying is more uniform from one mould to another than it used to be with the old style solid block moulds. The latter, being hinged and closing on an arc, had a tendency to squeeze the cherry away from the hinge and when this happened there wasn’t much to do but pitch the mould in the creek. Nevertheless, most of the old style moulds that finally got out of the factory were pretty good and some of them were excellent.
Hard spots in the blocks make trouble and blow holes in the castings may cause uneven cutting and necessitate recherrying. It is not possible by ordinary production methods to cut two cavities exactly alike except by chance but the differences between cavities cut with the same
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cherry are small indeed. In moulds having more than one cavity (for same bullet) the bullets will often be of different weights. When bullets of different weights are fired they will not shoot with the same elevation, that is, the heavier ones will shoot a little higher than the light ones. The difference can not ordinarily be detected by ordinary shooting but the reloader who wishes to get the most uniform results should use bullets from one cavity; it doesn’t matter which one.
Mould Repairs and Adjustments.
As has been stated, when a mould does not perform properly, the best bet is to return it to the manufacturer for correction. There is not much that can be done with the old solid block moulds. If a cavity is slightly burred, it may be possible to correct it if the present cherry is exactly the same shape as the one with which the cavity was originally cut, but recherrying these old moulds is likely to ruin them. Moulds of this type in common use are mostly Ideal moulds, made by the Ideal Manufacturing Co., by the Marlin Firearms Co., of New Haven, Conn., or by the Lyman Gun Sight Corp. when they first started making Ideal reloading tools. All the old fixtures for cherrying these moulds have been scrapped which makes recherrying them of uncertain outcome and the Lyman Co., will not do any work on these moulds except at the risk of the owner. Thus far they have been lucky, probably because they will not undertake such a job unless they are fairly sure that it can be done right.
The detachable mould blocks can be recherried at small expense either for the same bullet for which they were originally made or for a larger caliber bullet, provided the larger bullet is enough bigger and longer so that the original cavity can be entirely eliminated. It is not possible to recut a mould for a different shape of bullet of the same or nearly the same caliber.
It sometimes happens that a reloader is so situated that he cannot conveniently return his mould to the factory and an attempt will be made to suggest simple ways in which a cantankerous mould may be improved or a rusted or damaged one can be made serviceable. It should be understood that work of this kind had best be done by a skilled mechanic and the novice who tries it with poor results will have to take the responsibility, as no manufacturer will correct a mould that has been tampered with, without charge.
Venting. Probably the most troublesome condition in a new mould is the failure of bullets to fill out properly. Hollow point and hollow base moulds arc particular offenders, as the hollow point or base plugs cool more rapidly than the rest of the mould and have a tendency to cool the metal before it can flow into the narrow space left around these parts. Venting, hot metal and rapid casting will at least partly overcome this trouble. Failure of any bullet to fill out is caused by failure of the air to escape from part of the mould before the metal solidifies. It may be due to the metal not being hot enough or to the two halves of the block fitting too closely together. Bullets with narrow bands are special offenders.
An old trick for correcting this, and one that has some virtue, is to put a strip of thin paper between the two halves of the mould. This will make a slight gap between the halves for the air to escape through but it will also put the bullet slightly out of round. As a matter of fact, cavities often run a thousandth of an inch or so out of round and this is one of the reasons for making the moulds a bit over size so the bullets can be trued up by sizing them to the correct diameter later.
The best remedy is venting and to do a really good job of venting a small, fine cut, three cornered file should be purchased and prepared for use in the following manner: If the file has blank places near the end. grind the end back far enough so that there is cutting surfaces only on all sides. Then grind one side of the file flat and smooth. This will bring two edges down so the cuts on the other between the halves of the mould and the bullet can not be rotated nor the mould dosed tight.
Next, remove the bullet with the screw still in it and dip it in some flour of emery and oil or valve grinding compound; it doesn’t matter whether the latter is fine or course. Put the bullet back into the cavity but don’t close the mould tight enough to prevent your turning the bullet around with your fingers. Gradually increase the pressure on the handles again until the mould is apparently closed, then, open it, wipe off all the muck that has squeezed in between the blocks and repeat the process until you can turn the bullet with the mould fully closed. Why do I emphasize using the fingers to turn the bullet? Because it is only necessary to remove a little feather edge on the cavity and you don’t want to remove any metal from the cavity itself, as that will enlarge it. This is a simple operation but a delicate one so don’t put the end of the screw in a breast drill and grind for five minutes or so. A few turns of the bullet and lapping compound with your fingers will do the trick very nicely.
Rusted Blocks and Cavities. The above procedure can be used in cleaning out a cavity that has rusted. If the inside surfaces of the block are rusty, moisten them with oil or nitro solvent and go over the surfaces carefully with the flat edge of a screwdriver or a small scraper. You can easily remove the rust from the flat surfaces in this manner. If there is only a small spot of rust or two in the cavity you can best rub them out with a little abrasive on the end of a pine stick but if the rusting is bad, lapping with a bullet will have to be resorted to. It takes very little lapping to remove rust. After you have lapped a mould, wash it in gasoline to remove the lapping compound that may remain in the cavity.
If the mould cavity has been badly rusted and pitted, the bullets will have blotches on them. These will do no particular harm, but the pits may be rough enough to cause the bullets to stick. If, after you have lapped a rusty mould, the bullets do stick in the cavity so as to require undue pounding to get them out, prepare another bullet by cutting away the joint line and drilling it. Then put a light oil on it and stick it into some powdered graphite and proceed just as if you were lapping the cavity again, only this time don’t wash the cavity out. The graphite will pack into the pits and will remain there quite a while, as heat will have no effect on it and it will not adhere to the bullets. You will be surprised how nicely bullets will come out of an apparently worthless mould when it has been treated in this manner.
Misalignment of Blocks. Fins along the joint line of the mould are due to failure of the blocks to come together properly. The mould blocks are made of soft iron and the dowel pins which align the two halves of the block are of steel. If a mould is yanked open and slammed shut, as they often arc by the gentry who arc imbued with the idea that nothing connected with handloading is any good unless it can be done fast, a burr will be thrown up around the dowel pin holes which will prevent the two halves of the block from coming together. This is also the cause of some bullets being out of round, although a very slight eccentricity of bullets as cast is common and is one of the reasons for casting them over size, then trueing them up to the correct diameter later. Burrs around the dowel pin holes can be removed by filing them. Do not rub the file across the cavity and work slowly, with a sharp, fine-cut file.
Unfortunately, the improper use of a mould not only results in setting up burrs around the dowel pin holes but it enlarges the holes, causing a condition known as “shuck”, or an angular alignment of the halves of the block. There is no remedy for shuck except to return the mould to the factory. The pins must be removed, all the holes lined up and reamed out larger, and new and larger dowels fitted and this is no job for a novice without special equipment
Whatever. This extract comes from a version on the Internet Archive. When I drop this extract on a page, I will insert the images, which are well connected to the text...
v/r,
Elric
Handloader’s Manual - A Treatise on Modem Cartridge Components and their Assembly by the Individual Shooter into accurate Ammunition to best suit his various purposes
By Earl Naramore, Major, Ordnance Department Reserve, The Army of the United States
Sketches by LT. COL. Julian S. Hatcher
Small Arms Technical Publishing Co, Plantersville, South Carolina U. S. A. Sept 1937
Internet Archive, eBooks and Texts
https://ia800205.us.archive.org/1/i...1943/Handloaders_Manual_Naramore1943_text.pdf
Part II, Ammunition Assembly, Chapter 6, pages 183-201
THE CASTING OF BULLETS.
If all bullet moulds were the pink of perfection and if all bullet alloys flowed smoothly and alike and were the same temperature, the casting of bullets would be a very simple matter. It would only be necessary to melt the bullet metal, pour it into the mould and dump out a perfect bullet. While bullet moulds, as they come from the manufacturer today, cannot be considered as faulty and are very well made, each mould manufactured has its peculiarities and individualities. Different alloys of bullet metals do not all flow alike and cannot be used at a uniform temperature. Therefore, there is a little trick to casting good bullets that can only be learned by experience. While it will be possible to set down here certain principles, no amount of copy or directions can ever take the place of a few hours actual experience in casting bullets.
The materials necessary for casting good bullets are: a bullet mould; a dipper or ladle, preferably one made especially for the purpose as supplied by many of the reloading tool manufacturers and having a tubular spout, and a melting pot. A stout stick of wood about ten or twelve inches long is necessary for striking the sprue cutter; some wax or sal ammoniac for fluxing the bullet metal; a soft pad to drop the bullets on; an old box for the dross or oxidized metal that must be skimmed from the pot from time to time; and a source of heat for melting the bullet metal.
Source of Heat. The old-fashioned kitchen stove is sometimes criticized because of inability to control the heat accurately but this criticism is not justified because it is possible to control the heat of a coal fire by opening the drafts to increase the heat, or by checking the fire, or even by tipping the stove lids to decrease the heat and once the proper temperature of metal is obtained the even heat of a coal fire is very satisfactory. Of course, a gas or gasoline stove is more readily controlled and a little more convenient but is not a necessity.
Electric heating units are not as desirable as a gas flame as a general rule, for sometimes in casting bullets and in the preparation of metals and bullet alloys, an excessive amount of heat is necessary and electrical units are usually a little deficient in the heat that they produce. The ordinary electric stove is worthless, because the pot must set on top of the heating element so that only the bottom of the pot is heated while the greater area of the sides is cooled by the circulation of air. The small electrical bullet casting units are satisfactory in general but arc not adequate for preparing bullet alloys and when they arc used the bullet metal should be mixed and prepared over a hotter fire and then cast into small blocks of a convenient size for use in these small elements. A suitable' mould for the purpose can be made from a square box filled with damp sand pressed down firmly and with depressions made in the sand with the end of a broom handle. It should be borne in mind, however, that none of these electrical bullet casters have sufficient clearance beneath them to accommodate the conventional type of hollow-point bullet mould although they work quite nicely with all other types.
The principal objection to these electric bullet casters is that the metal is always drawn from the bottom of the pot. They are all made in the form of a small ladle or pot with a spout in the bottom. This little pot is surrounded by an electric heating element and is raised –up on a support so that the mould can be inserted beneath them with the pouring hole placed against the end of the spout. The spout is closed by a plunger passing down through the metal and the plunger is raised by means of a lever to permit the molten metal to flow out into the mould. To keep the alloy uniform, the metal must be fluxed and stirred frequently and with such a small amount of metal this cools the melt considerably. If the metal is not stirred frequently the lighter metals will rise towards the surface and a lead-rich mixture will be drawn from the bottom of the pot. They are, however, mostly satisfactory and are very handy for casting bullets, but like every other piece of reloading equipment they must be used with due consideration to the results that arc to be accomplished.
The ordinary melting pots and pouring ladles, while perhaps less convenient, will nevertheless, be best to use providing the source of heat is adequate, but here again they must be used properly. The larger volume of metal in the conventional melting pot can be kept at a more uniform temperature than in the diminutive electrical units and can be fluxed frequently without reducing the temperature of the melt below a satisfactory working point. But any advantage of the old fashioned lead pot is offset if the reloader continually dips metal from the surface of the pot, as is so often the case. Go to the bottom of your pot to fill your ladle as the movement of the ladle through the melt will help materially in keeping the metals thoroughly mixed.
Melting Pots. The lead pot should hold at least five pounds of bullet metal and preferably ten, as where the volume of metal is large a more uniform temperature can be maintained. This also permits the addition of new metal from time to time, without lowering the temperature of the metal below a set working point. Suitable lead pots can be obtained from any of the reloading tool manufacturers at small expense, while larger ones may be obtained from any plumbing supply house.
Pad for Hot Bullets. A pad must be provided on which to drop the bullets from the mould. The hot bullets are quite soft and are easily damaged and must not be allowed to strike a hard surface or to strike against each other. A piece of old blanket folded a few times is excellent but if a good blanket is used it should be covered with an old piece of cloth to prevent soil and scorch. If you have a work shop or arc situated so that you can have a few extra gadgets around without getting too many blessings from the family, a good bullet catcher can be made by stretching a piece of canton flannel, or any other soft cloth of good strength, across the top of a wooden box and tacking it in place around the edges. Bullets dropped on this will roll toward the center gently and when the accumulation of bullets becomes too heavy they can be removed carefully with a tablespoon.
Flux. Any kind of wax suitable for making bullet lubricant, powdered sal ammoniac or rosin make good materials for fluxing bullet metal. The waxes have a slight advantage in that the smoke produced can be ignited and burned; but you must resign yourself to some more or less unpleasant odors if you intend to cast your own bullets. Bullet alloys arc mixtures of lead and tin, lead and antimony, or all three of these metals. As the lead is the heavier of the three there is a tendency for the lighter metal to rise to the surface of the pot. The heat will also cause the metals to oxidize on the surface and these oxides form a scum on top of the metal that must be removed from time to time. The tin and antimony serve as hardening agents and they must not be skimmed off as this will change the hardness of the bullets. Fluxing the alloy will release the metals and leave the oxides in the form of black powder floating on top of the pot, which can be easily skimmed off with a bullet ladle leaving the alloy clean and bright. Experience will show the proper amount of fluxing material to use but the pot should never be skimmed without first fluxing the metal.
To do this, drop a piece of wax or a small amount of rosin or sal ammoniac into the pot and stir the metal rapidly. If wax is used, the gasses given off may ignite from the heat of the metal or can usually be ignited with a match, thus decreasing the amount of smoke and annoyance. The stirring will have a tendency to cool the mixture slightly and where the nature of the mould requires the use of a very hot bullet metal it is well to increase the flame under the pot, where this is possible, when fluxing. It is desirable to have a tin box at hand in which to drop the dross or oxides skimmed off but, as a matter of fact, any small box of wood or tin will serve.
Bullet Casting Procedure.
Now that we have all the materials at hand they should be arranged conveniently and the pot containing the bullet metal put over the fire to melt. If gas is used it should be turned up full till the metal is completely melted, after which the heat can be reduced as desired. The mould may be rested on the stove or placed close to the flame so as to heat up the block, but should not be allowed to get hot enough to burn any oil or grease that may be in the cavity.
When the metal is melted, put the ladle into it and allow it to heat. Then dip up some metal in the ladle, place the spout in a horizontal position against the pouring hole in the sprue cutter and turn both mould and dipper to a vertical position. Hold them in this position for a second or two. Remove the ladle, leaving some metal in the sprue hole. When the mould and metal are at the right temperature it will require a second or two for this excess metal to solidify but when first starting, the metal may solidify almost instantly due to the mould being too cold. The first bullets are apt to be misshapen affairs for the same reason. If the bullet metal is not hot enough it will solidify before completely filling the mould cavity. On the other hand, if the mould is too cold it will chill the metal before it has time to fill the cavity. When the mould and bullet metal are at the proper temperature it will require a second or two for the excess metal in the sprue hole to solidify after the ladle is removed. When the mould and metal are at such a temperature and the bullets do not fill out completely, it is usually due to mould blocks that fit too tightly together and do not permit the air to escape from some part of the cavity.
When the sprue has solidified the sprue cutter should be struck squarely with the stick and swung to one side, after which the mould may be opened over the pad, allowing the bullet to drop out. If the bullet does not drop out of its own accord, rap the side of the mould joint slightly with the stick of wood to jar the bullet out. Never stride a mould with a hammer or other metal object.
If the first bullets are not perfect, continue to cast them; they will get better and better as the mould warms up and you will shortly get perfect ones. As long as any oil or grease remains in the mould cavity the bullets will not fill up or they will be covered with small pits from the tiny gas bubbles formed when the hot metal comes into contact with the oil.
Breaking in a New Mould.
Most mould blocks arc made of malleable or alloy iron and come already blued or oxidized, so require no breaking in. If a mould cavity is bright it will not cast good bullets until the surface of the metal becomes oxidized. The ordinary procedure in such a case is to use the mould until the heat transmitted by the bullet metal accomplishes the desired result. This is often a long and tedious process and the job can be greatly hastened by placing the mould blocks on the top of a hot stove or by holding them near a gas flame until the cavity turns to a dark straw or blue. Before attempting to blue a mould cavity the mould should be washed in gasoline or carbon tetrachloride to remove all the oil, as the slushing oil used as a protection against rusting may carbonize and bum onto the mould. This will make blotchy bullets but the offending
carbon can usually be removed by rubbing with a soft cloth over the end of a wooden stick. It is a good plan to wash out any new mould, or any mould that has been oiled, before attempting to cast bullets with it. But if gasolene is used it should be outside of any room where there is an open flame. Gasolene is far more dangerous stuff than any kind of powder and the fumes carried to a flame by air currents have been responsible for many bad fires and fatal explosions.
Block Alignment. Contrary to popular belief a bullet mould is a precision implement and it must be used with reasonable care if it is to give long and satisfactory service. We all like to cast bullets with as much dispatch as possible but a little care in opening and closing the mould will not slow up the casting of good bullets to any appreciable extent and it will prolong the life of the bullet mould.
Most of the bullet moulds made today arc of the so called loose block type. The essential parts of one of these moulds arc shown in the illustration on Plate XIV. Each half of the mould block contains half of the mould cavity. Tins cavity is cut with a special reamer called a cherry which is made the exact shape of the bullet and no change can be made in the shape of the standard bullets, for which the manufacturers cut moulds, without making a new cherry which is an expensive job. However, some manufacturers will cut moulds for bullets that are longer or shorter than the standard, where the design of the cherry will permit.
The fit of the dowel pins on one block into the holes in the other block governs the alignment of the two halves of the cavity. When used properly there is very little wear on the holes or the pins but if the mould is yanked open and slammed shut, the holes will become burred at the edges and enlarged, which will throw the two halves of the block out of alignment and make it impossible to get perfect bullets from the mould. This looseness in the two halves of the block is known as “shuck” and can usually only be eliminated by returning the mould to the factory, having the holes reamed out larger and new dowel pins fitted.
Sprue Cutter Adjustment. The “sprue” cutter is a flat steel plate attached to the top of the mould block by a screw. The under surface of this plate fits closely against the flat top surface of the mould and forms the flat base of the bullet. The sprue cutter has a beveled hole in it, the bevel coming to a knife edge at the under side of the plate. This hole is the orifice through which the molten metal is poured into the mould and it is positioned approximately over the center of the cavity by a stop pin. The bevel of the pouring hole accommodates the dipper or the spout of the ladle, and the edge cuts off the “sprue” or overflow of metal after it solidifies.
The tension on the pivot screw of the sprue cutter should be sufficient to hold the cutter in firm aligning contact with the top of the block and if this screw becomes loose, metal is apt to flow in between the surface of the block and the bottom of the sprue cutter, forming a fin on the base of the bullet. If such a fin forms with the pivot screw reasonably tight, it is an indication that the sprue cutter is sprung and directions for attempting to overcome this condition are given elsewhere in this book. The stick of wood referred to above is necessary for striking the sprue cutter to cut off the sprue. Its size and shape are not important and any stick handy to use is all that is needed. A piece of old broom handle is excellent. Neither the sprue cutter nor any part of the mould should ever be struck with a metal object.
Corrosion of Moulds. Next to the individual who uses a bullet mould with more brawn than brains, the worst enemy of moulds is rust. Their oxidized film resists rust but will not prevent it. If you use your moulds frequently they can be put away with the last bullet left in them without opening the mould; that is, you can pour the mould full and leave it that way. This will exclude atmospheric moisture fairly well for a reasonable period of time under ordinary conditions but will not serve well where the humidity is high. When moulds are not to be used for a considerable period of time they should be oiled or greased. The grease or oil should be wiped off before using the mould again or, better still, washed off as already suggested.
CASTING TROUBLES AND THEIR REMEDIES.
Failure of Bullets to Drop From the Mould.
If the mould requires only slight jarring to make the bullets drop out, the condition can be ignored as a slight amount of “sticking” is unavoidable. The bullet usually persists in sticking in one certain half of the mould. Some operators tap the inside edge of that block with their stick—this is pretty apt to spring that half or cause it to warp open in time. Others tap the end of the handle in which half the bullet is stuck—this is apt to split that handle in time, but it can readily be replaced.
If one has to resort to pounding to get the bullets out there is something wrong and the mould will probably have to be returned to the manufacturer to have the defect remedied. The slightest damage to the sharp edges of the mould cavity will form a burr that will hold the bullets in and only an experienced mechanic can remove such a burr without damage to the mould. The average individual should not tamper with mould cavities in any way. Any manufacturer will correct a new mould that is at fault without charge, so it seems foolish to take a chance on ruining a four or five dollar mould.
Failure of Bullets to Fill Out. This is usually due to the mould, the metal or both being too cold. If the mould is too cold the metal will solidify before it has time to flow into all the comers. The net result will be the same if the metal is not hot enough. Sometimes mould blocks fit so closely together that the air cannot escape and with such a mould it is impossible to get good bullets unless the mould is “vented/’ Venting is done with a fine three-cornered file, with which shallow grooves are filed across the inside face of the mould blocks in such a way that the air may escape from the points where the bullet does not fill out properly. If the vents are filed too deep
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the bullet metal may flow into them when the mould and metal are very hot, but this does no harm as the projecting slivers will be sheared off when the bullet is sized. Venting can be done by anyone who is handy with a file but the file may slip and there is a good possibility that the file will burr the edge of the cavity. A vented mould is shown on this page which will serve better than a description of how the job is done. But remember—if a new mould does not cast good bullets the manufacturer will either vent it for you or replace it .
Bullets Out of Round. Due to shrinkage of some alloys when they cool, and to small manufacturing tolerances in the moulds, bullets may be a thousandth of an inch or so out of round as they come from the mould. They are purposely cast a little over size to permit truing them up in a sizing die of the correct diameter. If the variation in diameter is greater than two or three thousandths of an inch it may be due to a faulty mould, burred or enlarged dowel pin holes or to the presence of specks of lead on the inside faces of the mould blocks. Sometimes when dropping a defective bullet from the mould into the melting pot, lead will splash upward and small drops get caught between the mould blocks. These flatten when the mould is closed but hold the blocks apart enough to cause the bullets to be out of round. Such lead flakes are easily removed with a sharp knife.
Fins on Bullets. Mould blocks do not fit together properly or sprue cutter is not flat against top of mould blocks. If sprue cutter is loose tighten the pivot screw. If the sprue cutter is bent, remove it and try to straighten it with a light hammer. Then file the under surface flat, put it back on the mould and try it. If you cannot correct the difficulty in this way you will have to get a new sprue cutter. Burrs or raised metal around the dowel pin holes can be detected with a straight edge, they are easily removed with a flat file, hut care should be taken not to file across any part of the mould cavity.
Failure of Two Halves of the Mould Cavity to Coincide. The dowel pin holes are enlarged and the mould will have to be returned to the factory.
Frosted Bullets. When bullet metal cools it shows under the microscope as a crystalline formation. The size of the crystals depends upon the rate of cooling. If the metal cools quickly the crystals are small; if it cools slowly they are large. Bullets that solidify quickly in the mould will, therefore, usually have a bright shiny appearance but where the mould and the bullet metal are very hot and the metal cools slowly, the crystals will be so large that the bullet will have a frosted appearance. This difference in crystal size does no harm and has no affect on the performance of the bullet. If the mould and metal are allowed to cool down a little it will disappear but it must be borne in mind that some bullets with narrow bands, and especially bullets with hollow points and hollow bases, must oftentimes be cast with somewhat hotter metal than normal.
Folds and Seams. Either the mould or the metal is too cool.
Lead Smears On Top Surface of Mould Blocks. Usually caused by striking off the sprue when the mould
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is very hot and before the metal solidifies. This lead can usually be removed with a sharp knife when the mould is cold. It can also be removed with mercury. Be careful not to damage the edge of the cavity when you go to scraping around it with a sharp knife.
Elliptical or Lop-sided Bases. Generally confined to very soft bullets and caused by the base of the bullet being forced to one side when the sprue cutter is struck. See that the cutting edge of the cutter is sharp. It can be sharpened with a counter-sink turned with the fingers. If a soft alloy is used this defect can be reduced by closing the sprue cutter just far enough to allow the metal to be poured.
Hollows In Base of Bullet. These occur in bullets that are cast with a very hot mould and metal. The more slowly a bullet cools the coarser the grain structure will be and the more chance of the metal breaking off at the sprue. This leaves little crystalized depressions in the bullet bases. They do no harm other than to slightly reduce the weights of the bullets and only affect the accuracy to the extent that the weight of the bullet affects it.
Manufacture of Bullet Moulds.
Bullet moulds are ordinarily made from blocks of malleable iron. These blocks are machined to the proper shape and size and the interior surfaces carefully ground so that they will fit perfectly together. The two halves of the mould are then clamped together and arc drilled through at the proper points for the dowel pins and the corresponding holes in which the dowels are to fit. This insures perfect alignment of the two halves of the mould. A hole is then drilled in such a way that half of it is in each half of the mould block. After this the two halves of the block are brought together against a revolving cherry which is a special form of reamer that cuts a cavity the exact shape of the bullet. This sounds like a simple process and so it is to tell it on paper, but the operation is one calling for special skill and experience.
In the first place, a cherry is one of the most difficult reamers to make and frequently a lot of “fussing” is necessary before a new one will cut right. In making a cherry the stock is turned and ground to the shape of the bullet and to a size that will cut a cavity of the proper size. Ordinarily a cherry will not cut a cavity quite as large as itself unless allowed to run for an excessive length of time, and allowance must be made for this as well as for a possible shrinkage of the bullet alloy used. After the cherry is shaped the grooves must be milled in it longitudinally after which the real hard work begins for the tool maker. Merely cutting the grooves in the cherry will not leave it in condition so that it will cut, the ridges must be backed off before the cherry will cut, as the cutting edges or faces must always be the widest parts of the projections. This “backing off* is all careful hand work and the amount that the edges axe backed off depends upon the kind of metal the cherry is to be used on. For example, a cherry made for cutting cavities in malleable iron would not be satisfactory for use in steel or bronze and sometimes a cherry must be worked over several times before it will cut smoothly and without chattering. Even if the clearance is correct a cherry will chatter at times. If this happens when the cavity is nearly finished, both faces of the blocks must be reground and the cavity recut or the blocks may be cherried out for a larger caliber of bullet.
The older type bullet moulds had no detachable blocks, each half of the block being integral with one of the handles. The oldest ones had no dowel pins, but they were in general satisfactory. The objection to this type of mould was largely a manufacturing one for it was necessary to carefully fit the mould blocks before they were cherried and if anything went wrong with the cherrying the entire mould had to be scrapped. Furthermore, there was a tendency for the castings to warp under the influence of heat, throwing the two halves of the mould out of alignment. However, in spite of this many of these old moulds, including those that have no dowel pins, are still in satisfactory condition after years of use.
With detachable blocks, cherrying is more uniform from one mould to another than it used to be with the old style solid block moulds. The latter, being hinged and closing on an arc, had a tendency to squeeze the cherry away from the hinge and when this happened there wasn’t much to do but pitch the mould in the creek. Nevertheless, most of the old style moulds that finally got out of the factory were pretty good and some of them were excellent.
Hard spots in the blocks make trouble and blow holes in the castings may cause uneven cutting and necessitate recherrying. It is not possible by ordinary production methods to cut two cavities exactly alike except by chance but the differences between cavities cut with the same
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cherry are small indeed. In moulds having more than one cavity (for same bullet) the bullets will often be of different weights. When bullets of different weights are fired they will not shoot with the same elevation, that is, the heavier ones will shoot a little higher than the light ones. The difference can not ordinarily be detected by ordinary shooting but the reloader who wishes to get the most uniform results should use bullets from one cavity; it doesn’t matter which one.
Mould Repairs and Adjustments.
As has been stated, when a mould does not perform properly, the best bet is to return it to the manufacturer for correction. There is not much that can be done with the old solid block moulds. If a cavity is slightly burred, it may be possible to correct it if the present cherry is exactly the same shape as the one with which the cavity was originally cut, but recherrying these old moulds is likely to ruin them. Moulds of this type in common use are mostly Ideal moulds, made by the Ideal Manufacturing Co., by the Marlin Firearms Co., of New Haven, Conn., or by the Lyman Gun Sight Corp. when they first started making Ideal reloading tools. All the old fixtures for cherrying these moulds have been scrapped which makes recherrying them of uncertain outcome and the Lyman Co., will not do any work on these moulds except at the risk of the owner. Thus far they have been lucky, probably because they will not undertake such a job unless they are fairly sure that it can be done right.
The detachable mould blocks can be recherried at small expense either for the same bullet for which they were originally made or for a larger caliber bullet, provided the larger bullet is enough bigger and longer so that the original cavity can be entirely eliminated. It is not possible to recut a mould for a different shape of bullet of the same or nearly the same caliber.
It sometimes happens that a reloader is so situated that he cannot conveniently return his mould to the factory and an attempt will be made to suggest simple ways in which a cantankerous mould may be improved or a rusted or damaged one can be made serviceable. It should be understood that work of this kind had best be done by a skilled mechanic and the novice who tries it with poor results will have to take the responsibility, as no manufacturer will correct a mould that has been tampered with, without charge.
Venting. Probably the most troublesome condition in a new mould is the failure of bullets to fill out properly. Hollow point and hollow base moulds arc particular offenders, as the hollow point or base plugs cool more rapidly than the rest of the mould and have a tendency to cool the metal before it can flow into the narrow space left around these parts. Venting, hot metal and rapid casting will at least partly overcome this trouble. Failure of any bullet to fill out is caused by failure of the air to escape from part of the mould before the metal solidifies. It may be due to the metal not being hot enough or to the two halves of the block fitting too closely together. Bullets with narrow bands are special offenders.
An old trick for correcting this, and one that has some virtue, is to put a strip of thin paper between the two halves of the mould. This will make a slight gap between the halves for the air to escape through but it will also put the bullet slightly out of round. As a matter of fact, cavities often run a thousandth of an inch or so out of round and this is one of the reasons for making the moulds a bit over size so the bullets can be trued up by sizing them to the correct diameter later.
The best remedy is venting and to do a really good job of venting a small, fine cut, three cornered file should be purchased and prepared for use in the following manner: If the file has blank places near the end. grind the end back far enough so that there is cutting surfaces only on all sides. Then grind one side of the file flat and smooth. This will bring two edges down so the cuts on the other between the halves of the mould and the bullet can not be rotated nor the mould dosed tight.
Next, remove the bullet with the screw still in it and dip it in some flour of emery and oil or valve grinding compound; it doesn’t matter whether the latter is fine or course. Put the bullet back into the cavity but don’t close the mould tight enough to prevent your turning the bullet around with your fingers. Gradually increase the pressure on the handles again until the mould is apparently closed, then, open it, wipe off all the muck that has squeezed in between the blocks and repeat the process until you can turn the bullet with the mould fully closed. Why do I emphasize using the fingers to turn the bullet? Because it is only necessary to remove a little feather edge on the cavity and you don’t want to remove any metal from the cavity itself, as that will enlarge it. This is a simple operation but a delicate one so don’t put the end of the screw in a breast drill and grind for five minutes or so. A few turns of the bullet and lapping compound with your fingers will do the trick very nicely.
Rusted Blocks and Cavities. The above procedure can be used in cleaning out a cavity that has rusted. If the inside surfaces of the block are rusty, moisten them with oil or nitro solvent and go over the surfaces carefully with the flat edge of a screwdriver or a small scraper. You can easily remove the rust from the flat surfaces in this manner. If there is only a small spot of rust or two in the cavity you can best rub them out with a little abrasive on the end of a pine stick but if the rusting is bad, lapping with a bullet will have to be resorted to. It takes very little lapping to remove rust. After you have lapped a mould, wash it in gasoline to remove the lapping compound that may remain in the cavity.
If the mould cavity has been badly rusted and pitted, the bullets will have blotches on them. These will do no particular harm, but the pits may be rough enough to cause the bullets to stick. If, after you have lapped a rusty mould, the bullets do stick in the cavity so as to require undue pounding to get them out, prepare another bullet by cutting away the joint line and drilling it. Then put a light oil on it and stick it into some powdered graphite and proceed just as if you were lapping the cavity again, only this time don’t wash the cavity out. The graphite will pack into the pits and will remain there quite a while, as heat will have no effect on it and it will not adhere to the bullets. You will be surprised how nicely bullets will come out of an apparently worthless mould when it has been treated in this manner.
Misalignment of Blocks. Fins along the joint line of the mould are due to failure of the blocks to come together properly. The mould blocks are made of soft iron and the dowel pins which align the two halves of the block are of steel. If a mould is yanked open and slammed shut, as they often arc by the gentry who arc imbued with the idea that nothing connected with handloading is any good unless it can be done fast, a burr will be thrown up around the dowel pin holes which will prevent the two halves of the block from coming together. This is also the cause of some bullets being out of round, although a very slight eccentricity of bullets as cast is common and is one of the reasons for casting them over size, then trueing them up to the correct diameter later. Burrs around the dowel pin holes can be removed by filing them. Do not rub the file across the cavity and work slowly, with a sharp, fine-cut file.
Unfortunately, the improper use of a mould not only results in setting up burrs around the dowel pin holes but it enlarges the holes, causing a condition known as “shuck”, or an angular alignment of the halves of the block. There is no remedy for shuck except to return the mould to the factory. The pins must be removed, all the holes lined up and reamed out larger, and new and larger dowels fitted and this is no job for a novice without special equipment
