I have a Kahr MK9 that has a tendency for the slide to lock back prematurely, before the magazine is empty. It will even do this with my arm and wrist locked out (I'm 6'3", 230 lbs, so I don't have a problem holding it firmly). I realized that the slide retention lever's spring wasn't pressing down as much as I thought it should and so I reasoned that the lever must be flipping up with the recoil. I contacted support and they sent me a new spring (thank you!), but the spring they sent me was the wrong one (oops!). So rather than go through that again, I took the original spring out and gently bent it so that it would press the lever down more firmly. I finally was able to get to the range last week and I had the same problem, it was raining so I didn't put a lot of rounds through, but it locked back on me once in two magazines. Any other ideas? Oh yes, and it will do this with standard pressure el cheapo FMJ rounds as well as high quality high pressure JHP rounds. If all else fails, I'm going to buy an extra slide retention lever and file down the bit that holds the slide back! A few compact guns down even offer slide lock, so why not?