Last i checked up on it the 762x39 ammo was getting harder to come by, esp with all the sanctions on russian made ammo? Haven't looked in a while though as don't shoot it anymore.
300blk is in the same ball park as 762, however you get the added benefits of shooting subsonic hunting rounds. Also much more projectile selection if you were to delve into reloading, or knew someone that ran the calibre to load for you?
Else if you want versitility, ammo availibility and huge variety off the shelf then i'd be going for a .308. There not as good as a 300blk with subsonic ammo, however you can do it, and you can stretch your shooting range out much further with them. When Hornady does finally get there A into G, and start producing enough of the SubX projectiles to sell them for reloading then the .308 would be awesome with them loaded up.
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