Range Report Springfield Armory M1A -07-21-2010

[Phineas Bluster]

Deleted

[TCLouis]

You would have to post this.
There is one listed on the 24 Hour site complete with mags and scope mount that keeps calling my name.
I don't need it or have a real use for it, but it is as close to a M-14 as I can afford!

[Larry Gibson]

Also try 28 & 29 gr loads along with the 30 and 31 gr loads. Your 32 gr load is pushing 4 moa and perhaps even more as range increases. With the 180 gr bullet the 28 gr load with the dacron filler should give reliable functioning. The 28 -31 gr loads should also improve on accuracy as velocity drops back down. What is the twist of your M1A barrel?

Larry Gibson

[Mk42gunner]

Larry, shouldn't M1A barrels be 1 in 12"? That is what I always haerd the M-14 barrels where.

Robert

[nicholst55]

Larry, shouldn't M1A barrels be 1 in 12"? That is what I always haerd the M-14 barrels where.

Robert

Military barrels are 1-12"; many commercial are 1:10", with some others 1:11".

[Larry Gibson]

Phineas Bluster

Nothing wrong at all with the 12" twist milsurp barrels, I actually prefer that twist. That was the standard twist for M14 barrels and most rack grade replacement barrels are 12" twists. The 10 and 11" twists were used back when match shooters found the 168MKs to be in acurate at 1000 yards from M14s. The 10/11" twists were used because they would stabilize the 180 MK and some thought the faster twist would also stabilize the 168s. That was before they knew about the buffering the bullet took dropping back sub sonic. Anyways it was known that many times the 12" twist was more accurate at 600 yards with the 168s and the 174 gr bullets of M118 Match ammo than the 10" twist barrels. The 11" twist was the comprimise so the one rifle shooter could still shoot the 180s at 1000 yards. Even with that many times scores weren't much better over those with M118 Match. The advent of the Sierra 175 MK negates the need for any twist faster than 12" in M1As. That 12" twist will provide the best stability to to the 175MK out to around 1100 meters befor it goes sub sonic given a velocity of 2550 - 2800 fps from an M1As 22" barrel. The 175Mk is the bullet for the .308W for any longer range work (exception being Palma matches where there is a max weight restriction of 155 grs). My tests have also shown that the 12" twist provides the best stabilit based on the BCs. With Identical loads and velocities the BCs of most 10/11" twist barrels run in the .48 to .49s and with most 12" barrels the BCs are .51 - .52+. Those are consistant across several different rifles of each.

Back to your cast load; The 180 RCBS bullet should stabilise without problems in your 12" twist even at lower velocity. It is a good weight for the M1A the trick being to get accuracy with reliable functioning. Appears you are on the right track. Please keep us informed of your progress.

Larry Gibson

[cast367]

Phineas Bluster,
I use in me Winch. M70 , 180grs Rcbs, Hornady gascheck,30/70 % lino/pure lead.
19 grs Acc. no. 9. Its give an 2" result at 100 meters.
When I use the 200 grs Lee with 17 grs no.9 is a same 2"group possible.
Rifling 1-12. I use dacron filler.Case Berdan primed.
Maby load will not repeat in a M14. I have only bolt rifles.

[mroliver77]

It's looking like your gun likes the 32 gr load. I use a harder boolit than you and get good results. I have a SA "NM" and a Polytek that has a TRW bolt, USGI shimed gas system, NM trigger job and glass bedded into a big ole walnut NM type stock. Both are fairly easy to find 3moa loads with cast. I use nothing but Felix lube and rarely clean the barrels unless I shoot jacketed. The chrome lined Chinese barrel does not seem to ever foul with anything. Larrys 28gr 4895 is a good place to start. I have a few kegs of 2520 I got very cheap and have had some good results with this if I use hard boolits, dacron and push it some to make the ball powder burn well. I am actually surprised how well it does burn for downloaded ball powder.
Jay

[mroliver77]

I went back and reread the posts. I dont see a boolit size listed. I run mine .310 or .311 to get good results. I was running over 30 gr of 4895 and Larry sugested the 28gr load. With enough dacron to fill the case well this load works good. I get a little better groups than you are shooting only at 100 yards. Keep us posted of your results.
Jay