casting .308 bullets

[462]

Definitely some serious seating problems that need to be remedied.

If it were me, I'd start by setting the Dillon dies aside, buy a Lyman or RCBS neck expander die of the appropriate size (31 plug for the Lyman) or as fiver mentioned earlier a Lee collet neck sizing die, and one of the many brands of in-line seater dies, then modify its seater plug to fit the nose without leaving a trench round it.

Ian asked: "Do you have one of tha Lyman cast bullet manuals?"
Both the 3rd and 4th editions have much need-to-know stuff.

 

[fiver]

Dillon does make their stuff some tight.
my size trim die in 308 gives me like 303 interior diameter whereas my 0-6 trim die would give me 305.
even for jacketed I need to use an appropriate expander ball.

their seating dies etc are great but they have their sizing dies set up to make 100% sure you can run them through a semi auto without fail.
you might shorten case life but they will chamber and fire 100% of the time every time all the time.
as you can probably tell they are not catering to the cast bullet crowd, more like the ipsa and 3 gun types that burn through crates of ammo.

 

[Ian]

Some of this makes sense I’m using a progressive press from Dillon with Dillon dies same set up I use for the jacketed Bullets so thinking one will work why not the other I have a RCBS single stage press and will try that

Going back to this again. We need to start over at the very beginning and go over CAST BULLET handloading step by step.

 

[tuckerjoy]

No only book I have is Modern reloading second edition by Richard Lee and Lyman 50th edition I will start looking for this book that I need. I just use the Dillon press for every time I pull the handle I got a loaded shell. I never size nothing just jam the bullet in the neck and head to the range.

 

[waco]

I never size nothing just jam the bullet in the neck and head to the range.

And this is a lot of the problem you are having with your accuracy. Too much neck tension and possibly shaving some lead. A neck expanding die helps out lots. You had mentioned you had 10-15 Thou runout as well. A good inline seater die is invaluable. I like the Forster Ultra Micrometer dies.

 

[Ian]

Maybe you should read the one you have. I don't have Lyman 50 but do have a 45, 47, and 49 and they all have chapter on the tools and techniques required for loading cast bullets in both handguns and rifles. You should avail yourself of that information and study the illustrations and then you can see some of thebthings you're doing completely wrong, and unsafely as well.

 

[fiver]

cast bullets are a whole new world.
as you have seen they work and can even shoot very well.
you just need a new mind set and perspective when looking at tools and measurements.

 

[tuckerjoy]

I read it and I slugged the barrel just like it said then you tell me that is not what you do you need to measure the throat. So which one or both.

 

[waco]

I read it and I slugged the barrel just like it said then you tell me that is not what you do you need to measure the throat. So which one or both.

I have never slugged a rifle bore. I size the bullet to fit the throat. No issues to date. YMMV

 

[gman]

What the guys here are trying to tell you is that loading for cast is a whole different animal than loading for jacketed bullets. The reason they had you pull that bullet was to see if the bullet has been swaged down from seating it in the case neck. From the picture it is obvious it is. With cast bullets it's important to size your bullets to fit the throat. Same if shooting cast in a revolver. Forget about slugging the barrel for now. Take a bullet that you have sized and lubed and measure the diameter. Then take that bullet you pulled and measure it. It's going to be smaller by looking at that picture. That's a problem right there. I use 3 different Dillon loaders and I can assure you that the Dillon dies are not set up to load cast unless you are loading the same diameter bullets as the jacketed bullets you may have loaded before. Case prep is more critical with cast to make sure you can seat your bullet without scrapping lead and having the right amount of case neck tension. Now you can still load cast on a Dillon but you will need to use different dies to size with and to expand the case mouth so you don't shave off lead from the bullet when seating and you have the proper neck tension. I'm certainly no expert in loading cast for AR's but regardless the firearm the bullet must fit and also loaded properly. It's easy to get overwhelmed with information but what the guys here are good about is trying to help you start thinking about what you need to do. In other words they are helping you to learn yourself by giving you information. The first book I bought and studied and still study at times is the Cast Bullet Handbook. Hang in there with your project. You have lot's of help here!

 

[fiver]

the reason to slug the barrel is just so you can find tight or loose spots.
it also gives you the diameter which is handy to have.

information.
information is good.

I have never slugged a barrel either [shrug] I could I got the stuff I have never had a barrel that needed it.

what your doing with the throat.
and why it matters.
after doing a pound slug you can see 'stuff'
shape, imperfections, diameters, tapers, etc.
what it will tell you right off is that it doesn't have 2 parallel sides.
it has the end of the chamber [letting you know just how short your over long case necks really are]
the leade and the throat taper into the rifling.

making an outline on a piece of paper will show you a picture of what your working with in reality.
and where you need convex shapes to fill those little tapers.

in reality your gonna find something similar to the above
or something like below.

 

[fiver]

good perspective Gman.
I too load some of my cast bullet rifle loads on a Dillon.
nuthin I want to drive over 2-K fps or make little 1/2" groups with [although the 300 will still stack them in there even on the Dillon]
even there I'm not using Dillon dies or straight up off the shelf Dillon powder funnels.

 

[tuckerjoy]

Ok gentlemen here we go again I just mad a mold of my throat it measures .311 so now do I buy a mold to fit my throat or do I get some measurements at different places of this mold

 

[tuckerjoy]

I wrote mad I meant made

 

[tuckerjoy]

Here is a picture of what I got setting in a cut off shotgun shell and I have been reading and trying to understand casting rifle bullets

 

[fiver]

you need more measurements.
lay the slug down sideways on a piece of paper and outline it.
now you can 'see' a clear picture of what your working with.
start taking measurements along it's length and make notes on the drawing of where and what you measure.

you'll have something like a progression of 311-310-3095-309 then hit the rifling.
your probably not gonna see a long parallel section in there.

 

[tuckerjoy]

Ok I started measuring at top of the neck and it measures .314 then move out just kinda like the picture shows and it .311.5 next is .308.5 then when I believe it is at the rifling it measures .307.5. I believe this is how the picture showed to do it

 

[freebullet]

When all else fails & info overload ensues....go shoot!

 

[fiver]

the picture above is the saami specifications for a 308 rifle.
your is quite similar just a little bigger so nothing out of the ordinary.

take your measurements.
and draw a picture of a bullet .001 smaller than what your getting.
include the slope from one measurement to the next like your connecting the dots.
taper it down to the centerline of the bore and that will tell/show you what your bullet should look like for a good static/mechanical fit.

 

[fiver]

the next step is to then compare your drawing to the bullets we recommended earlier in this thread.
remember some of the actual bullet diameters can be slightly manipulated with alloy changes.