I have a 4" GP 100 and I changed the grips out and put Pachmayr finger groove grips on it last night. Then the wierdest thing happened. It functions, but it has gotten very tight to cycle. When I pull the trigger, there's lots of resistance and the cylinder is very tight to turn. The trigger pull is off the charts. I pulled the grips back off and pulled the hammer spring, hammer and trigger group and everything seems normal. I cleaned the parts up, lubed the trigger group and reassembled it. Same problem. So I disassembled it and reassembled it several times, all with the same result. I am completely stumped. Obviously the grips have nothing to do with the operation of the revolver, so it just doesn't make sense. It seems that I'm missing something, but I haven't a clue. Does anyone have any suggestions? And why would such a thing happen in the first place? BTW, this is the first .357 I ever owned. I had an opportunity to buy it back from a buddy. I had it to the range last weekend and it shot fine. I plan on using it as my woods gun for if and when we ever get to Oregon.