Went to fire my Great Plains flintlock rifle today and found that when I use the set trigger the lock stops at half cock. I took it apart and looked at the fly. Seems okay and the lock works as it should out of the stock. Took the trigger out and it seems to be functioning. I put the lock back in, with the trigger still out and pushed the post with a screwdriver. The lock operated as it should. I put the trigger back in and pulled the hair trigger hard and found that yes, the lock works that way. The only way it does NOT work is with the set trigger. Any body got any ideas? If I do it 5 or 6 times it will sometimes work with the set trigger. Which kinda means to me that something is out of adjustment, but what?