A while back I obtained an L&R RPL lock for an old Dixie Tennessee Rifle with the idea of converting from cap gun to flint. Installed the lock and had nothing but trouble. The 3/4" flints that I had were too long, and the lock wouldn't fire but a couple of times before it would quit for the day. Sent it back and they re-treated the frizzen and, I think changed out springs. When I got it back it was pretty much the same as it left. After much tinkering with it I had almost given up, then ran across the "I Hate This Lock" thread. That caused me to believe that perhaps the frizzen was too hard, so I stuck it on the lower shelf of the oven and set for 450 deg. Since I didn't want to heat up the whole oven for a part about the size of a key ring, I thought it would be a good idea to throw in a couple of skillets that could use re-seasoning. 450 is too hot for a skillet. I'm not sure just how long it was treated for because when the house filled with smoke the wife turned off the oven. the polished face of the frizzen was sort of a brown color, so I figured I was OK. Thought it was better that maybe she really didn't have to know what the cause was........Anyway, reassembled the lock and just for good measure jammed a piece of leather in the bend of the mainspring because it still felt a little weak. I also got some 5/8" flints. Now, after three range sessions, we have not experienced any failures and it is still on the first flint. In a weird kind of way I am happier with it now than I would have been if it had worked right out of the box. Sort of odd for a lock I was about to drop into the parts box.
Just goes to show, Live and Learn and never quit.