Lyman’s GPR hammer needs adjusting

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timetraveler

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Hello all, first post. I have an older GPR and the hammer doesn’t come down on the cap cleanly. It needs to be moved forward or bent open a little. Right now the front rim of the hammer hits the cap first but the hammer force pushes it the rest of the way down. The gun fires fine but I’d like to fix it but don’t know if it’s possible. Can a gunsmith heat the hammer and bend it open a touch? I don’t see any other way. I saw an offset nipple but the threads were different. Anyone have a suggestion? Should I dremel the front rim off so it doesn’t skip off it? Don’t really like that solution either. I got to say the gun is a shooter, I’d like to fix it.
Thanks, glad I signed up. I actually did years ago but never posted and when I tried to sign in it wouldn’t let me.
 
Yes, @timetraveler, the hammer can be heated and bent to properly clear the nipple for a solid strike. This was often a necessity for CVA hammers in the kits sold in the 1970's. The whole rifle needs to be used as the test fixture when bending the hammer to be sure the cup is centered on the nipple.
 
Thank you guys, that’s what I wanted to know. Don’t know if I should do it myself though. I’ll ask a gunsmith I heard about.
Thanks again
 
Try unthreading the nipple 3-4 turns to make it longer and let the hammer down (without a cap) on it to see where it hits and see if it's worse or better. That way you can see if a shorter or longer nipple may work. A longer or shorter nipple may fix your problem depending on the arc travel of the hammer.
 
No, longer or shorter nipple won’t work. When I started trying to solve this problem that was the first thing I looked at.
Then I thought maybe moving the whole lock set, trigger assembly forward or just the hammer forward but everything is such a tight fit I don’t think that’s possible either, But, I haven’t taken anything apart yet to know for sure.
Can you still get replacement parts for the GPR still? What if the gunsmith wrecks my hammer😵‍💫. Maybe I need a blacksmith 😝
 
Yes, @timetraveler, the hammer can be heated and bent to properly clear the nipple for a solid strike. This was often a necessity for CVA hammers in the kits sold in the 1970's. The whole rifle needs to be used as the test fixture when bending the hammer to be sure the cup is centered on the nipple.
Back in the late 70's and early eighties I assembled several CVA kits for the local Amish boys and almost every one needed the hammer aligned with the nipple. I used a map gas torch to heat the hammer in the area to bend and then bent it placing a box end wrench over the hammer, Then when I had it aligned I sprayed it with WD40 while it was still hot to give it a nice Color bluing .Some times I had to square up the hammer face to the nipple. I would do this by placing a thin brass spacer in the hammer after "tinning" the hammer with solder, setting the tinned hammer with the spacer on the nipple and heating it with a common propane touch enough to melt the solder, Then let cool . You have to be careful and not have too much solder in the hammer
 
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