so i was at the range today and i was shooting my model 65. i had shoot 20 or 30 rounds when all of the sudden the pistol completely locked up! hammer wont move the cylinder wont advance trigger wont move!! it could not get it open!! there was an older gentlemen to my left a couple lanes down shooting some big bore revolvers so i asked him for advice and he pulled out a rubber mallet and lightly tapped the cylinder and it popped out. we inspected the rounds and found the one that was causing the jam. where the firing pin hit the primer it had bubbled back out (from compression i suppose) and when i tried to advance the cylinder it jammed. he said that i might have a weak spring for my hammer and to replace it. what do u guys think about it? oh after that i shoot about 30 more rounds threw it to see if it would happen again and it didn't?? any ideas? should i replace the spring? how much would that cost??