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So I'm thinking about building a Krinkov, but I'm not sure whether I should go with 5.45 or 7.62. I've ruled out 5.56 since the 8 inch barrel would more than likely kill any possibility of bullet fragmentation past 50 meters. Does anybody here know the effect of an 8 inch barrel on a 7.62 and a 5.45 round? Does the 5.45 round depend on muzzle velocity for terminal performance like the 5.56? I would assume so, but I know the 5.45 has no fragmentation properties so I'm not sure. My guess is that the 7.62 would suffer the least from a shortened barrel since the bullet has quite a bit of mass. Kind of like the .357 vs .44 snubby debate. Anybody have any difinitive answers or insight?

I'm told I'm going to be OpFor for these guys. I was curious if anybody has been stationed here or knows someone who has. What are the facilities like? What is the job like? Off time? How's the area and nearby towns?