Derringer Lock Problem

[Ironhand]

When I tried to fire my new Derringer I discovered that the lock would not fire the caps consistently. I pulled the lock to see if I could adjust it and discovered this unusual coil spring lock.

As you can see the front surface of the sear strikes a post on the lock plate to stop the forward rotation of the hammer. I believe that if I grind away some of that contact surface the hammer will rotate further and strike the cap harder. It looks like the area could be ground down using a Dremel tool without even disassembling the lock.

Gunmakers, what say you? Would this plan work?

Ironhand

[gunmaker]

Is that a CVA product ?  I had one, never would pop caps.  I made a washer to go behind coil spring to stiffen it up some--worked then, never thought a grinding stop down. looks like tumbler's rubbing the plate by the scratch arc, that'll slow down hammer strength for sure.   ..Tom

[Captchee]

i would look at your nipple first . possibly it needs a new one or a taller one . my concern with grinding the tumbler is that as the tumbler travels forward more , the post engagement of the spring also has to have more pivot . without that , you may end up bending or breaking the end of the rod the spring surrounds Or have the post come completely out of the   tumbler . IE notice  that one the first photo , the end of the spring rod  is at  an angle that appears to leave very little room for any more  travel of the tumbler

[Ironhand]

Good point Captchee. I will try a new nipple first. I would rather not work on the lock if I don't have to.

Thanks
IRONHAND

[rollingb]

Looks to me as though the end of the lock bolt may also be hitting the hammer,....
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