Hold Open

Don, Since both of your existing mag are Mec-Gar, you may want to try a different brand, perhaps triple K or one of the orig or EG Schmeisser types. You didn't mention trying different types of ammo. This can also make a big difference. The ammo that you need, must have enough power to set the breechblock back far enough for the hold open to engage. Also, check the cut on the bottom of the breech block. If it is rounded perhaps the holdopen is slipping off. Trickey beast, these PO8s.