M1 Carbine shell sizing

Been working on a load for the good old Carbine.
Slugged and found it shoots best with .310 boolets.
Lyman 311359. IMR4227.
When I full length resize the shells, and reload, there is a step where the boolet seats in the shell.
I full length size for all semi autos I have.
This last reload I decided to only resize enough to hold the boolet.
Will try it this Sunday.
Just trying to get the last bit of accuracy out of it.
Shoots great at 50yds, expect it to do better at 100yds.
I've tried Blue dot, Win296, Unique,.

I'm not so sure if partial sizing of the case will really help with accuracy.

What type of accuracy are you getting right now. My best shooting carbine will shoot 10ring if I do my part. The carbine I have been shooting cast with is more like some 9 and 8s.

Yes, there will be a step because the case is designed to take a .307-.308 bullet. Yours in larger than that so you get the step. I've sized mine up to .311 and it still works.

You will get your best accuracy from the NOE 311115 and 296/H110.

The 30 Carbine is the only 30 Cal that I size to .309. If I go bigger than that in my Inland it wont cycle smoothly at all.

Remember, the carbine case is a tapered case, not a parallel sided straight wall. If it isn't sized down enough, the bullet will fall back into the case. You can get into serious trouble if the case isn't tight enough and I'm not talking about just the case mouth. BTW, the carbine takes a .3075 dia bullet, not a .308 so .309 is fine.

Well it didn't work like i thought it would.
Seems the very slight taper in the case aids in feeding.
I had a few that did not pick-up through the mag.
Not sure why it is, but didn't have it happen when full length sized.
As far as accuracy, not much difference.
I'll go back to full length size and just live with the funny looking shells.

1680 is an exceptional powder in the 30 carbine as well.

1680 seems to be the same burn rate as 4227.
Has anyone tried IMR4198?????
I'm wondering if it might be to slow burning.

What bullet are you using?

Larry Gibson

Lyman 311359.
I tried a plain base 120gr and it just wasn't as accurate.

I tried 4198 years ago under the 311359......did indeed prove to be too slow......

I also size .309 BTW.

Larry Gibson

Quote:

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Originally Posted by abunaitoo

Well it didn't work like i thought it would.
Seems the very slight taper in the case aids in feeding.
I had a few that did not pick-up through the mag.
Not sure why it is, but didn't have it happen when full length sized.
As far as accuracy, not much difference.
I'll go back to full length size and just live with the funny looking shells.

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Make sure your mag springs are in correctly. They are designed to keep the back of the case up in the mag. If the spring is turned around you'll get fail to feed problems.

It was the shell sizing.
Haven't had a problem since I went back to full sizing.

I was getting a bulge in case that corresponded to the bottom of projectile. Wound up backing off my sizing die slightly & bulge went away. Loaded rounds still cycle, chamber & fire in my Inland & AMT. I checked how well brass grips projectile, can't budge it with pliers or push it back so good enough for me. IMR 4227 works good in both.

One thing I've noticed, at least with FMJ bullets, is that case bulge is often "off center". I purchased a Lyman M Die, and I suspect that will remedy it, but I've not loaded any 30 Carbine after I purchased the M Die.

My best results with FMJ's has been with AA#9. I'm looking forward to casting for this caliber because I have way more 30 Carbine brass than any one person should own. :smile:

Did the Unique actually properly operate the action? I've seen data for it listed in lots of manuals, but I've never tried it myself.