Yeah, the "7.62" line is confusing. There are lots of "7.62's"!
I will comment that a bolt rifle in 7.62x39mm is a dandy little rifle to an extent and suitable for whitetails and hogs, possibly black bear. Cheap to shoot (can we say that anymore?) with mild report and recoil. Great starter centerfire as long as the range is not to great, and pretty useful as a GP piece as long as you don't need .308 win or '06 power, and most of us don't most of the time!
Some (not many) may be bored .308 instead of .311 and if so can use commonly available .30 cal slugs, and may shoot .308 dia well enough for plinking anyhow. For a while I loaded my Ruger bolt so chambered with 147 gr GI FMJBT and shot very cheaply. In those days I could get 1000 slugs for well under $100. I did not want to shoot import steel case ammo thru that particular rifle.