Next gun... What should it be?

.308

7mm

Either would do fine. I'd lean towards .308 since I already have 2 .30-06 rifles. :P

308 is pretty much the standard for long distance shooting, a lot of the military uses it for engagements 500+ yards out

Yeah, .30-06 and .308 are ballistically very similar. The .30-06 is an older cartridge and a solid hunting round. The .308 is used in the military and has a little bit longer reach for long range targets. Not to say .30-06 isn't usable out to 500+ yards, but the .308 does slightly better.

.223 :)g)

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