I've had about three dozen of the OLD original AI built AR 10s, both Sudanese and Portuguese.
I've fired several thousand rounds through these old timers, mostly cheap 7.62 NATO ball, but also lots of factory .308 WIN, mostly 168 gr MATCH ammo,
and at least a thousand rds of my own reloads. In my experience, the older AR 10s often shot 7.62 NATO BALL ammo just as accurately as they did the 168 gr Match .308 Win ammo.
If you intend to reload for the AR 10 rifles [ and also the M14 rifles] both of which have floating firing pins with no springs, I would advise using the HARDEST commercial primers you can find, as both the M14 and the AR 10 design will lightly dimple the primers when they feed the round into the chamber. If you use the stronger/thicker 7.62 NATO brass, make sure you carefully remove any crimp in the primer pocket.
If you shoot reloads through these type of rifles, always check each primer by running your finger over the back of the loaded cartridge, to make sure the primer is FULLY seated, below the end of the case. When I reload for the AR 10 and the M14, I usually seat the primers with a LEE hand tool, which provides a very CONSISTENT "FEEL'. And if you use 7.62 NATO brass for your reloads, remember it is thicker, so drop your max loads down accordingly.
For all these reasons, rather than reloading, I prefer to shoot cheap Walmart/ Canuckistan Tire or Gunshow bargain factory ammo out of my semi auto rifles.
NOTE: because of the stronger / better rotating bolt design, the AR 10 rifles can handle heavier bullets better than the M 14. My newer style DPMS built AR 10/ R25 shoots factory Winchester 200 Gr Silvertips under 1". It also shoots 125 gr factory ammo into about the same size. And the same for 168 gr Match.
BTDT,
these opinions are based on my own persoanl experience,
however,
YPMMV
LAZ 1
