.300(300 weatherby) is a hunting round really. bit more grain, packs a nasty punch in the 3-600yd range. My dad has two 300’s single bolt action, and a double barrel breach. I’ve shot both of those guns and they’re a hard hit to the shoulder. there is a .300 Rxx cartridge that’s supposed to be good but I’ve never seen nor fired it. Something with different grain count and fast burn powder.
the .308 is the tried and true sniper round. Typically good for 7-800yds, after that it’ll start falling like a brick. People say it’s accurate to 1000yds but that’s REALLY dependent on the rifle and shooter and at that range inst going to have nearly the punch. If I had my choice though, .308 all the way. rounds can be found EVERYWHERE as it’s a standard NATO round, 7.62x51mm. I’ll go to garage sales and see misc .308 stuff for 50 cents a clip. I have all the crap here to reload .308 as well. Probably have 50lbs of clean brass here in the basement, dad likely has primers and rounds around here as well. 1/2 our rifles here shoot .308
You and I think alike in rifles Chris. that SIG is second on my list of small caliber rounds. I’m still looking at a used TAC 50 though :excited