Hi, I am new here. I have 3 LB's, a Premier II in .38 Super, a Super Tac in .45 and a new GT Monolith Stinger .45 (standard weight.) The Premier II and Super Tac work flawlessly. The GT MS seems finicky with ammo. I called and spoke to Les, I have tried the ammo's he suggested but still have the same problem. Wondering if anyone else out there has had this trouble. The slide will stay open with rounds still in the magazine. This is not a feeding problem. The magazine release/stop lever simply engages, and the slide then stays open. I will release the lever, as one would normally do, and the slide goes forward and I can keep shooting until it does it again. However, upon close inspection, I can see that the lever does not go all the way up into the notch on the slide. With the last round fired and the magazine empty, the lever DOES go all the way up into the notch to hold the slide open. I have tried about 15 or 20 different factory ammo's which will do this. (I should add that all of these various rounds will shoot just fine in my Super Tac; in fact, they will shoot just fine in all my 1911's except this GT Monolith Stinger.) I have 5 different magazines for this, all LB mags, it doesn't matter which one I use. I am stumped. Any thoughts?