I just acquired an FN Browning 1910/22. It works fine except for one thing. The safety notch that is closest to the muzzle will not line up with the safety. It won't go back quite far enough. I assume that this is because the slide is not the one issued with the pistol but comes from a different 1910/22. (It doesn't have a serial number stamped on the underside of the slide.) The only difficulty this causes is in disassembly and assembly. Since the safety can't hold the slide in position, I have to hold it by hand--77 year old pencil pusher hands! A conceivable solution is to widen the notch so the safety will go in. But like you all, I am creeped out at the thought of permanently altering an old firearm. Is there something that I'm missing here? Something I don't understand? [Edit: I just checked. The slide does in fact have the same serial number. I guess I'm blind as well having other problems.]