This is one of those imponderables.................. We're not actually looking at the problem as such, but the variables. Give us your views on these Chinese conversions MGMike. Have you seen any/many? They look interesting.

I always remember back to 15 or so years ago when a load of blank ammo was doing the rounds. It was from.............. well, nobody ever could tell but the end of the boxes was marked green white green and some wag suggested that it was Nigeria - or Kenya or, well, anywhere really. But even the best Brens and GPMG's coped to struggle with it most of the time. We thought it was filled with chipatti powder but every so often you'd get one filled with TNT.............

What I'm saying in a very roundabout way is that not all 7.62 x39 is made to NATO spec!