.............I have a SA with a stainless NM bbl, but it's not match bedded or anything. I wanted to be able to take it apart if I have to, and not worry about the bedding. I have three M1 Garands. Two '43 produced SA's and a '55 HRA. Some may laugh, but the Garands were all eager to please, but this M1A was an equine of an entirely different hue.
I read all the "Danger Will Robinson" warnings about possible primer issues, and possible commercial brass problems also. So far no problems. I should have bought a lottery ticket at the same time I bought 1K LC-18, and 1K LC-19 7.62x51 milsurp brass. They were all primed (YAY!) and had the black asphalt sealant in the case necks (which turned out to be a PITA). This was all like 6 hours before the Chinese Communist Whuhan virus BS erupted, and all the IDIOTS and MORONS lost their freaking minds and ran around in circles crying, "MY GOD, MY GOD, we're all gonna die".
In any event, I suppose the reason these lots of military brass was surplused was due to primer issues, otherwise the brass was great, but primer performance not so much. Glad I'm not big on sitting in front of the IDIOT BOX (wife takes care of all the TV watching) so I ran all the brass through the Dillon to de-prime. Then they got tumbled (rotary) in really hot water with concrete floor cleaner and stainless pins added. They were absolutely dazzling. It was kinda like a second freaking career but got it finished. Then I ran them all past a primer pocket swager to get the pockets ready.
I was always one to partake of the surplus market so I have several jugs of milsurp 4895 AND WC846, which also was a powder used in the 7.62x51. Having several friends who were also casters and reloaders, we could practically put together some truckload orders in years past. Another was 4475, which is now commercial production and labeled 5744. Speed is/was similar to 3031. Not being bashful about stocking up I had quite an assortment of primers on hand. Paying close attention to what I'd been told I laid in a good supply of those CCI #34's to go with the rest. The bullets used in testing were Hornady #3037 150gr FMJBT all from the same lot. All seated to have a nice crimp applied into the crimp groove. Then a test was performed a couple weeks later.
The load for them all was 43.0grs of Canister IMR 4895, same bullets & powder for all, just a different primer for each batch of 20 rounds.
FIRST UP: were the UNIX-GINEX (Serbia Milspec) primers. These things required a BUNCH of effort to seat. AVG 2772 fps ES 71. All 20 rounds fired, no problem.
SECOND UP: CCI #34 Mil Spec primers. A little effort to seat. Had 4 fail to fire. Retry and 3 fired on 2nd hit. One wouldn't go off at all. 2765 FPS. Also produced the highest extreme spread of 103 fps.
THIRD UP: RUSSIAN PMC. Okay to seat. 19 fired, 20th fired on 2nd hit. 2765 FPS, ES 58 FPS.
FOURTH UP: FEDERAL LR MAGNUM: Easy to seat, all 20 fired first time. 2821 FPS, ES 85 FPS
FIFTH UP: WLR STD PRIMER: SEATED normally all 20 fired normally. 2799 FPS, ES 70 FPS.
Winchester factory 7.62x51 Factory Brown box. Caseheads stamped WMA-16. 19 of 20 fired. 1 dud. 2823 FPS, ES, 95 FPS.
That magazine on the M1A is nice, and maybe I'll get it figured out, but my lord! Those Garands were sure eager to please compared to THIS contraption!
..................Buckshot