[buckweet]

So, there I was, at the range last Saturday... my first day with that pretty little lady, the SA M1A.

Loved it! I was borrowing it from a friend, who was nice enough to hand it over along with a CASE full of Brazilian surplus ammo.

Having pretty good results at 100 yards, no complaints for the first time out with her. So I try switching ammo-- just to see.

I load up a mag full o' my premium boxed ammo-- PMC loaded with Sierra MatchKing 168 gn. BTHP, and lock her into place.

Squeeze the trigger... and... BAM! First shot-- right in the bullseye. But I notice that the bolt hasn't locked in place. The mag dropped down about half way out of the well, and had mashed one of those Sierra beauties into the wall.

Went back to Brazilian, no problems... tried the PMC again, the mag drops out again.

Now, I know these aren't hot rounds-- I've been using them without a complaint in my Rem 700 for the last 2 years.

Any thoughts???

 

[Harley]

Can't help ya Buckweet. I haven't had that problem. All I know is that I've experienced some problems too, and it seems as though M1A's are rather finicky about what you feed them. You just have to try different ammo manufacturers till you find one that your rifle likes.

 

[Shootist3006]

What is hot in a 700 and what in an MiA are two very different things. For the M1A, a 168 gr. bullet should have a MV of about 2700 fps - not much above that. Also check which powder you are using, it should be one of the mid-range burners, not a slow burner.

 

[Harley]

Good point Shootist3006, that could be a big part of my problem. The last time I loaded a batch of '06, my buddy insisted that I should aim for 2900-3000ft/sec. because he said "military ammo is hotter" and the M1 Garrand and M1A won't cycle properly unless I duplicate the pressures/ muzzle velocity. We were feeding 4 different rifles; an M1 Garrand, an M1A National Match, a Browning BAR, and a Ruger model 77. The M1A was the only rifle that I had problems with. Like you said maybe that batch was just too hot?:sniper:

 

[Tailgunner]

7.62NATO data
M59 and M80, ball ammo specs call for a 150 gr bullet @2750
M118, Match ammo is 175 gr bullet @ 2550
M852, M14 National Match ammo is a 168gr HPBT @2550
30-06 data
M2 ball 150gr bullet @2740
M72 Match/National Match ammo [email protected]
All velocities are +- 30fps and are measured 78 feet from the muzzle
Specs taken from COTW 9th ed

 

[Robert D. Lyons]

The military doesn't load their ammo hotter than the commercial manufactures. When reloading for my M1As and M1 Garand I load the 150 grain bullet to around 2650 fps. I use W748, AA2460 and other powders with a similiar burning rate.

 

[Harley]

Tailgunner, thanks for the specs. So hotter ain't necessarily better. I knew I was doing something wrong. I got a deal on 8lbs. of Accurate 4064 and a 1000 Nosler J4 comp 168 gr. hpbt bullets, so I'll be playing with some lighter loads and see what kind of accuracy I can get out of 'em.:sniper:

 

[buckweet]

Thing is, (and thanks for all the replies, guys) I wasn't shooting handloads. I was shooting factory loaded PMC w/ Sierra 168gn bullets-- at 2650 fps.

Just curious, really. I plan to start handloading my .308, but for factory ammo, the most accurate round I've found was that PMC stuff... I'd be bummed if I couldn't use it in my M1A.:sniper:

 

[Robert D. Lyons]

Buy Hornady's 5th edition reloading manual. It has sections specifically for the M1A and the M1 Garand.