I went through this in Feb 2014. I shoot 6.5x47, 300wm, 30.06, .270, 6br, 6dasher bolt guns, and my M1A's, FAL, and ARs. If I HAD to pick one can to use on ALL of them, I would choose a SWR Specwar7.62. Heavy…yes..but its full auto rated and has minimal POI shift. I fortunately had enough...