M1A load

24 February 2021, 23:12

cal pappas

M1A load

Gents:
I loaded some .308 cases for my new M1A. 180-grain Norma bullets and 39 grains of 3031 powder.

The powder was probably too fast for the action to work properly. The fired case was ejected but the bolt did not move far enough back to pick up the next round in the magazine. (Years ago I had the same problem with my M1 and a move to a slower powder solved the problem. But the .308 case does not seem to be able to hold enough 4831).

What powder and load would you recommend? I do have 4831 and several of the Reloader series of powders.

Thanks for your help.
Cal

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Cal Pappas, Willow, Alaska
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25 February 2021, 00:19

tsturm

quote:
Originally posted by cal pappas:
Gents:
I loaded some .308 cases for my new M1A. 180-grain Norma bullets and 39 grains of 3031 powder.

The powder was probably too fast for the action to work properly. The fired case was ejected but the bolt did not move far enough back to pick up the next round in the magazine. (Years ago I had the same problem with my M1 and a move to a slower powder solved the problem. But the .308 case does not seem to be able to hold enough 4831).

What powder and load would you recommend? I do have 4831 and several of the Reloader series of powders.

Thanks for your help.
Cal

Try Varget if you have some, Ramshot Tac, RL-15?

25 February 2021, 07:20

richj

IMR 4895 classic powder for M1A 308.

25 February 2021, 07:23

cal pappas

Thanks, gents. I will try both 4895 and RL-15.
Cal

25 February 2021, 09:33

KY Nimrod

Yep IMR4895 or AA 2520 for the 168s. For the 180 grain loads you will want to try IMR 4064 It will give you the correct pressure curve for a M1A and a little more velocity with the heavier bullets than 4895

25 February 2021, 10:12

MikeBurke

This article is the gold standard for reloading the M1A

http://www.zediker.com/downloads/14_loading.pdf

4831 is too slow for the reasons Zediker explains

Do you know the twist rate? 180’s might be borderline heavy depending on twist.

25 February 2021, 17:37

jeffeosso

h335 or tac - i'd aim for duplicating milsurp loads

26 February 2021, 05:27

KY Nimrod

quote:
Originally posted by MikeBurke:
This article is the gold standard for reloading the M1A

http://www.zediker.com/downloads/14_loading.pdf

4831 is too slow for the reasons Zediker explains

Do you know the twist rate? 180’s might be borderline heavy depending on twist.

I agree with this 100% 4895 has been the go to powder for highpower match shooters with M1As for a long time. Back when I was competing I wore out three M1A barrels using a hefty dose of 4895 behind a Sierra 168 match king. But as I shot into master class I wanted a little more edge at 600 and would shoot the old version of the 180 SMK for the 600 yard event. Today, there's really no reason not to use the 175 gr Match King across the course. As mentioned in the article, stay away form slow powders in the M1A...its not that they are unsafe but they tend to beat up the gas system and bend the operating rods...which are hard to replace these days with reproduction parts and impossible to do so at a reasonable price with non-existant USGI parts...

28 February 2021, 05:00

LeonardC

Your 3031 should have worked with lighter bullets, 150 and 168's.

I burn more 4064 (both IMR & AA) than anything else. It's at the top end of the "slow" powders, but has been good for me.

About any of the powders within this range should work for you. I think IMR 4895 is pretty much the standard.

28 February 2021, 19:51

john c.

quote:
Originally posted by MikeBurke:
This article is the gold standard for reloading the M1A

http://www.zediker.com/downloads/14_loading.pdf

thanks. downloaded it to read later.

4831 is too slow for the reasons Zediker explains

Do you know the twist rate? 180’s might be borderline heavy depending on twist.

03 March 2021, 01:59

Gundog 64

Cal,
42gr. IMR 4895 and a Sierra 168gr. Match King. If your rifle does not shoot that load well, sell it or take it to a competent M1A smith (they are getting hard to find, the smith that is).

13 March 2021, 03:44

MoreBS

Hodgdon Reloading Data Center has 308 Service Rifle data.

13 March 2021, 22:38

loud-n-boomer

quote:
42gr. IMR 4895 and a Sierra 168gr. Match King.

A half grain above what most manuals list as maximum, but the standard .308 service rifle match load for years. In addition to the above, I have had good luck with 41.0 grains of IMR 4064 with the same bullet.

19 March 2021, 18:25

RPSnell

Hornady has loads for the 308 Winchester Service rifle.

20 March 2021, 21:06

KY Nimrod

quote:
Originally posted by loud-n-boomer:
quote:
42gr. IMR 4895 and a Sierra 168gr. Match King.

A half grain above what most manuals list as maximum, but the standard .308 service rifle match load for years. In addition to the above, I have had good luck with 41.0 grains of IMR 4064 with the same bullet.

For me it was 42.5 of 4895 with the 168 smk in a GI case. It was a little warm but not ridiculous and I probably shot 20,000 rounds of my reloads with that combo in my M1A. The 175 SMK was not available back when I was competing but if it were it would have been all I would have used. Its a superior bullet in a .308 at 300 yards and beyond. Beats the pants off the 168 at 1,000 yards for certain.

22 March 2021, 23:54

MikeBurke

quote:
Originally posted by KY Nimrod:For me it was 42.5 of 4895 with the 168 smk in a GI case. It was a little warm but not ridiculous and I probably shot 20,000 rounds of my reloads with that combo in my M1A. The 175 SMK was not available back when I was competing but if it were it would have been all I would have used. Its a superior bullet in a .308 at 300 yards and beyond. Beats the pants off the 168 at 1,000 yards for certain.

Sierra recently came out with a 169 grain bullet with a better bc, stays supersonic past 1000 out of a 308.

Looks like a good bullet for the M1A across the course also.

28 March 2021, 18:19

KY Nimrod

If you look at the boattail profile on the SMK 190 its the exact same profile as the 175. Back in the early 1990s Sierra made the 180 SMK with the same long boattail and then for some unknown reason changed it to the short boattail profile found on the 168 SMK. Now it seems they figured out they are losing market share to companies like Berger and Hornady with very sleek long range bullets with high BCs and they finally changed the 168 to the long boattail profile as well.

We trudge on...