Cap problem???

[barebackjack]

Hey all,

I went for one last range session last night with my GPR before deer season opens up tomorrow. I havent shot it in a couple months and havent had any problems with it till last night.
I recently installed a flash cup on it, I noticed that I wasnt able to get the capper on the nipple far enough to fully push the cap onto the nipple. First shot was a click, second shot went off fine. So I pulled the cup (gonna file a bit out of the front so I get in there).
Loaded up again, capped like I always have, first shot, click, second shot (same cap) no problem. I started pushing down on the cap harder and harder, same results....cap, cock, squeeze, click, re-cock, boom. Never once did the gun fire on the first try, but always fired flawlessly on the second try.
Now these caps have been in the capper in my shooting bag for a couple months in my house. Could they have gone bad?
Also, is it possible to push so hard on a cap while putting it on the nipple to actually make it fire?
As I said season starts tomorrow, and I cant get a new nipple as nobody in town carries them and I dont have time to order.

Anybody got any suggestions?

Thanks much
Boone

 

[Norskie]

Look at the hammer face. There might be cap debris hiding in there. Also try a little light filing on the nipple itself. It may have mushroomed a little and you're not getting the cap seated.

 

[Blizzard of '93]

Both of Moose's suggestions are good, and you might try slowly lower hammer on cap and push firmly to seat cap, doubt that it will go off, I do that with my C&P revolvers , in order to seal against moisture (point in safe direction of course) and no 'bangs' yet.

 

[Rebel]

I've got caps that were in a capper for over a year and they go off fine, so i doubt that is the problem. Sounds like you need to file the nipple a bit to let the cap eat fully. Or try a new nipple on it.

 

[paulvallandigham]

I find that heavy main springs on Percussion guns bang the heck out of nipples, even my Stainless steel variety. You might just replace that nipple and then see how well the caps fit. You should see a little bulge for just below the top edge of the nipple, as it the column is collapsing. That will be the clue that the niplle is being abused. You can simply replace nipples often, or consider reducing that mainspring tension. You need less than 10 lbs to set off a cap, and I am willing to bet that your spring has a lot more tension than 10 lbs. My brother has reduced the mainspring on one of his percussion guns to leas than 7 lbs, and he has no trouble igniting percussion caps at all. His nipples do now seem to last indefinitely.

 

[paulvallandigham]

I find that heavy main springs on Percussion guns bang the heck out of nipples, even my Stainless steel variety. You might just replace that nipple and then see how well the caps fit. You should see a little bulge for just below the top edge of the nipple, as it the column is collapsing. That will be the clue that the niplle is being bused. You can simply replace nipples often, or consider reducing that mainspring tension. You need less than 10 lbs to set off a cap, and I am willing to bet that your spring has a lot more tension than 10 lbs. My brother has reduced the mainspring on one of his percussion guns to leas than 7 lbs, and he has not trouble igniting percussion caps at all. His nipples do now seem to last indefinitely.

 

[pmwest]

Sounds like the nipple is damaged or worn out and should be replaced. With no replacement immediately available, I would find a whetstone or emery paper and chuck the nipple in a drill (but not on the threads) and grind the nipple back to a cone so that the cap will seat fully. One thing that I do on my cap guns when hunting is lower the hammer on the cap and push to make sure the cap is fully seated on the nipple.

 

[redriverclerk]

Is it the factory nipple? My father and I have the same problem with our GPR's - his is 6 years old, mine less than 6 months. He "seats" his cap on the nipple by manually pressing the hammer down, then recocking and firing. I gave up on that approach and replaced the nipple with an after-market and haven't had to reseat the cap since (about 50 rounds on after-market nipple). I thought maybe Lyman had a manufacturing problem with their standard nipple...

 

[dmills]

I was having same problem with GPR .54 and one particular stainless nipple. I changed to a new nipple and solved problem.

Since you do not have a spare, you can put the threaded end of the nipple in a drill chuck and use a file on the side of the nipple to dress. Look closely at the nipple first and you will probably see some slight deformation on the side of the nipple close to the top.

I keep one nipple in the rifle, 1-2 spares in the range box and one in the hunting kit.

 

[BrownBear]

Did you ever drop the hammer on the bare nipple while installing and removing the flash cup? In my experience with the GPR and Lyman nipples, you only get to do that once before filing/replacing the nipple. The tolerances on mine seem a bit tight, but if I damage the nipple even slightly, I immediately get your symptoms. My shooting pard switched to hot shot nipples of some sort and has never been bothered since. My next move!

 

[Keppy]

barebackjack
I also had the same problem a while back that you are describing. I found that the nipple was mushroomed enough that the caps would not seat. As others have said, I filed it with a small stone I have. Be sure not to get carried away or they won't stay on. I'm still shooting the same nipple and works fine. Never dry fire it without a piece of leather over the nipple. I take a piece of leather and punch a hole in it to go over the nipple. I make sure that its high enough so that when the hammer falls it falls on the leather and never able to touch the nipple. I store my rifles like that,with no tenson on the spring. Good luck. Hacksaw

 

[barebackjack]

Thanks for the advice everybody.

I did some scrubbing on it last night with some emery cloth, and it seemed to do the trick. I am going to get a replacement nipple or two for it as soon as I can though.

I do not recommend poppin caps inside though, those things are LOUD indoors. Lol.

Thanks again for the help.

 

[renovato]

I had to replace the nipple on my GPR almost immediately. It never did fire right and rather than keep tinkering with it, it was easier to just replace. Looks like you're in a similar situation.