223 AR15

[Brad]

Just finished casting some RCBS 55 SP bullets. Plan to shoot them from my AR 15.

Any suggestions on loads? I have lots of RE7,15,and 19 powder. My favorite powder, 2400, will get some trials too.

AR is a very accurate rifle. Is easily capable of sub MOA at any range to 600. This was my completion rifle for NRA service rifle so I fully know what it can do with jacketed but it has never been fired with cast.

 

[Ian]

You know I got nuthin', but am going to watch this one with interest because I have an old Colt rifle with a 7-twist HBAR, and that same mould.

 

[300BLK]

I'm going to suggest Reloader 7. Reloader 15 and 17 were too slow for my 9 twist with 73gr cast. Try 14gr Reloader 7 and work up 1/2 gr at a time. Depending upon gas system length, it might work with 2400.

 

[Brad]

The rifle has a full length gas system.

I was planning to start with RE7, it can do well at lower pressures and can also give all the velocity I need.

 

[300BLK]

waiting for fiver to chime in with his data

 

[Brad]

waiting for fiver to chime in with his data

Me too.
I know he has been there and done that. First thing he will stress is rigorous sorting of bullets

 

[Brad]

Sized a few tonight. My Lyman likes to size them in a most decidedly non-concentric manner.
I think I will wait til I can make a push thru sizer or a die for my Star before I mess with things. Taking good bullets and ruining them via sizing just doesn't make sense to me.

 

[Ian]

Might have to seat the checks first, I know I did, then through the Lee sizer they went, and finally on to the Lyman 45. Anyone want to buy a 450 cheap?

 

[Brad]

Checks were a bit snug. I can easily whip up a mandrel to flair them and fix that issue.
I need to order a lap to polish a sizer and a drill bit close to finished size. Should have a sizer whipped up in a week or so.
I need to slightly change the seating stem on my Forster ultra seater, it leaves a small ring on the nose of bullets.

 

[300BLK]

I have a pair of 450s. I put a little bullet lube on the top punch stem and don't tighten the screw. Likewise, I don't fully tighten the die retaining nut so that it can float a little. My AR has about a .227" throat and I've seen mention of them as large as .229". My bullets drop real close to .2265" and my die is right at .227", so not much sizing going on there.

 

[Brad]

My Lyman die is .225. I will be making a few push thru sizers the a star die and can easily go bigger.
I never thought of keeping the lock ring loose so the die can float a bit. Good idea. The top punch isn't tightens at all, I like them to float.

 

[Rick]

My Star dies have never been tightened and the top punch has never had a lock ring on it. Tighten the die enough and you can make it oblong, let the punch float and find it's own center.

 

[Brad]

I was speaking of my Lyman, not my Star. My Star doesn't have a way to tighten a die and the lock ring for the top punch is in the garage by the lathe to make sure the threads are right when I make a new punch. Had to find some use for it.

 

[fiver]

I forget the thread pitch on the star punches but it's sumthin goofy like x24 or x26
anyway weight sorting will for sure help,, toss the heavy and light ones. [and sort into .1 weight groups]
if you munch, fold, tweak, or fight with a gas check,[other than tapping them into place] toss the whole thing back in the pot.
I actually use the punch to press the checks on straight [base down on a piece of steel over the size die] then run them through the sizer.
this is a case where I go to my 4/6 alloy, you need the extra bit to align the bullet with the nose, and cannot rely on a mechanical fitment.

forget faster powders.
748, 4895, varget is where you want to be.
start at about 18-19 grs and move forward those loads should shoot well and be on the verge of [or have] full function.
I stopped at 22.5 grs of imr 4895 in LC cases.
20-21 grs of 748 should be a good load, and varget would be in the 23-24gr range.

.225 should work fine for functioning and is where I stopped since my mold barely makes bullets over that size, and the drag in the sizer really helps seat the check square.
.227 would work with some scuffing and is a great diameter in a bolt gun but not an AR.
226 might be best but I didn't want to rough up the bullet in the 5.56's throat [the sizer would just barely touch it anyway]
and rely on the nose shape to get things aligned [hence the harder high tin alloy]

 

[Phil]

I have had good results with the 62 grain "NATO" bullet and 19.3 grains H4895 in my 16" carbine. This 100 yard target is one of the better but not unusual for the load. I would like to think the two fliers were me and not the load but who knows. Other targets show 1 or 2 fliers per 10 shots as well. But those are only an inch off the group so not bad. That was with Felix lube and homemade copper gas checks.

I have not yet tried that load in my new AR rifle build.

 

[JonB]

I forget the thread pitch on the star punches but it's sumthin goofy like x24 or x26
anyway weight sorting will for sure help,, toss the heavy and light ones. [and sort into .1 weight groups]
if you munch, fold, tweak, or fight with a gas check,[other than tapping them into place] toss the whole thing back in the pot.
I actually use the punch to press the checks on straight [base down on a piece of steel over the size die] then run them through the sizer.
this is a case where I go to my 4/6 alloy, you need the extra bit to align the bullet with the nose, and cannot rely on a mechanical fitment.

forget faster powders.
748, 4895, varget is where you want to be.
start at about 18-19 grs and move forward those loads should shoot well and be on the verge of [or have] full function.
I stopped at 22.5 grs of imr 4895 in LC cases.
20-21 grs of 748 should be a good load, and varget would be in the 23-24gr range.

.225 should work fine for functioning and is where I stopped since my mold barely makes bullets over that size, and the drag in the sizer really helps seat the check square.
.227 would work with some scuffing and is a great diameter in a bolt gun but not an AR.
226 might be best but I didn't want to rough up the bullet in the 5.56's throat [the sizer would just barely touch it anyway]
and rely on the nose shape to get things aligned [hence the harder high tin alloy]

Is your 4/6 alloy = 90/4/6 (Pb/Sn/Sb) ?
Or 4 parts this and 6 parts that ?

I ask, as I bought an AR-15 (DPMS 1/9) this weekend at the gunshow...I sold the one I use to have a couple years ago during the crazy prices after Sandy Hook....couldn't resist. I recently read of someone casting pure lino for AR shooting, and that kinda made since to me...I have plenty of lino, but sadly my lino has been ingotized by myself, before I knew better, and I blended all the spacers strips (maybe 25%) with the actual linotype strips from the 120lbs that I bought back then...so I suspect it's not as hard as Lino should be...You can bet, I'll be checking that out (measuring hardness), as I learned of this mistake and have since not used any of that lino. Even more sadly, I am quite sure I didn't blend the batches anywhere nearly uniformly and I didn't keep the batches of ingots separated. I can only hope that the particular spacers I had were very near normal linotype alloy and not softer like some reportedly are. I should be able to determine that with alot of hardness testing.

anyway, I ask again, is pure linotype a good idea for casting for the AR ?

 

[300BLK]

I don't cast anything with lino or mono. Almost all of my rifle bullets are water dropped with low Sb and Sn. Adding Cu into the mix will increase the hardness and malleability rather than being brittle.

 

[Phil]

I cast 22 bullets in pure lino. It casts so nice and uses so little per bullet that after trying it years ago I have stuck with it. The bullets used on the target two posts up were pure lino.

 

[Ian]

I cast 22 bullets in pure lino. It casts so nice and uses so little per bullet that after trying it years ago I have stuck with it. The bullets used on the target two posts up were pure lino.

If you were to shoot a group into a catch medium of some sort, you may find some bullets missing the back half, cracked in half at the lube groove. Linotype and the deep-groove 45 2.1 designs don't necessarily go together very well in my experience. You might have better luck with water-quenched or heat treated clip-on wheel weights plus 1% additional tin, that will get you the same BHN or higher and flow much better through the rifle's throat.

 

[Phil]

If you were to shoot a group into a catch medium of some sort, you may find some bullets missing the back half, cracked in half at the lube groove. Linotype and the deep-groove 45 2.1 designs don't necessarily go together very well in my experience. You might have better luck with water-quenched or heat treated clip-on wheel weights plus 1% additional tin, that will get you the same BHN or higher and flow much better through the rifle's throat.

Thanks for the suggestion. Maybe fractured bullets are the cause of the fliers. However I would think they would be far worse than an inch from the group.

Anyhow, I'll try a different alloy the next time. I have a good supply of COWW and lino. What may be a good mix? I have quenched my COWW in the past for 30 cal and they do come out very hard but does not cast the little 22s well without help from lino or tin. I have no more straight tin.

Maybe 75/25 COWW/lino and quench? Somewhere I have a calculator to provide guidance. However, my stock of COWW seems harder than suggested in web sources. I believe COWW composition varies greatly and to go by web composition values is a fool's game.