I have a Newer style Stainless Contender frame that I bought a few years back. Took it to the range yesterday and it would not cock consistantly. As I started to pul back the hammer, there was a click and it would pull back, but not lock as if the trigger had been pulled before trying to cock. I clicked the action open and tried again, still click and not lock, it locked back on the 3rd try, any suggestions would be sincerely appreciated. I tried 3 different barrels and it did it on all barrels.