Originally Posted by pranc2
i have also heard that weapons made for .308win have problems shooting 7.62nato were as weapons made for 7.62nato can shoot either round with no problems.
The two caliber designations can be confusing to the common shooter who does not have the right info about the two types of calibers. They look the same to the naked eye but what sets them apart is the thickness of the brass and the pressure each is loaded to. The 308 Win's brass walls are a bit thinner than the 7.62 NATO because it has a lower pressure than the 7.62 NATO. If the gun doesnt specifically say 7.62x51 NATO on the gun then it wont cycle it as easily and isnt safe to use with the higher pressure. The firearm may survive the higher pressure but only for a short time because technically you'd be shooting a higher pressure than its designed for.
Surplus ammo for my FAL is something I havent looked into yet, I'm working on getting a new receiver before I do. I wont shoot anything but 308 Win in it because if I were to use the higher pressure it would start to develop hair-line fractures in the receiver.