Just shot my vector v91 with the mp5 style short cocking lever front end. loaded an old aluminum and a steel mag with different rounds, mixed 7.62 and 308.
not one thought of an issue, first mag break-in style. second mag as fast as I could shoot it. then a 10 round cheap plastic. not a blink. perfect shooting rifle.
glad I didnt go the 53 way. but I do have a .40 mpg vector coming. ready for anything, but happy the rifle worked.