Great Plains RIfle - New Nipple Must Snap Cap Twice

[F_Thomas]

OK guys, I have changed the nipple and then reworked it with a file and I am getting hammer strike and no bang. Is this caused by something out of adjustment or is the spring weak?

It is ruining my target fun!!! Don't want to take it hunting until the problem is resolved.

I thought that I had worn a nipple out. Guess not!

 

[F_Thomas]

One other thing. Where can I get the schematics for the Great Plains Rifle Percussion?

 

[Oldnamvet]

The GPR uses a coil spring for the lock and they rarely get weak. What size caps are you using? If you are using #10 you may have to hit them once to get them fully seated and the second time to fire them. I use #11 caps on mine. Also check to see that the interior of the lock is clean and free of residue, bits of cap, etc.

 

[necchi]

Common problem with the Lyman and T/C locks,
This photo is a T/C but your is close;

The arrow is pointing at the Fly Detent under the bridle plate (removed for photo).It just drops in a little hole in the tumbler, it's job is to let the trigger sear skip over the half cock saftey notch when you pull the trigger.
IF the bridle plate screws are the tinyest bit loose, the fly will cock out of position and stop the hammer just short of striking the nipple. It looks, sounds and feels like a full drop, but the hammer is stopped short.
The Fix; The lock comes out of course. Check those 3 bridle plate screws,(T/C has only 2) use a proper bit and get them tight. Clean and lube the internal lock parts, it takes a few drops of oil to do the job. I put a drop right on that fly, and another that hits the back side of the tumbler, some on the trigger sear pivot and that plunger,,(too much is too much, don't get carried away).
If it's the first time the lock is out, it's a good idea to spray the entire thing with some brake cleaner, the factory lube is awfull heavy and picks up gunk really easy (grease an grit is a bad thing) slowing things down. While it's out clean up all those wood chips an burr's left in the mortice from the machining.
Cleaning and care of the lock on these things is part of it too, I do mine 2-3 times a season just to keep it in top shape. :grin:

 

[Semisane]

Necchi nailed it. Odds are those screws are not tight.

 

[F_Thomas]

Just pulled it apart and cleaned it up and re-lubed. Needed it. Checked the screws and they were tight, but there was a slight worn spot on the hammer that I couldn't notice with it together. However, once everything was tightened up and the put back together it seems to be hitting harder than it had. I'll check it out again in the am and blow some caps when the neighbors aren't around. City living is not for me!!!!!!

 

[necchi]

I had a dickens of a time with one Lyman/Investarms fly.

I finally took it out and polished the side that contacts the sear, actually filed on that one side a bit and then polished.
Course, I'm notoriuos for taking factory locks fully apart and smoothing/polishing the parts that rub against each other. I just do the finish work the factory doesn't take time to do.
I think they call it "tuning" a lock,? :idunno:
But ya gotta be carefull, some places you dont wanna take any off.

 

[bobman]

with my GPR I have to press the caps on the nipple firmly then its fine so you might want to pay closer attention to how you are placing the cap on.

I use 11 caps and have only fired mine about 25 times the nipple is getting flattened.

I also used a bucnh of caps that I purchased in 1977 and they all fired except one.

 

[jbtusa]

I would check to determine if there is wood inside the lock mortise that is slowing down the hammer fall. Use a china marker pen to coat the inside of the lock's moving parts and then cock the hammer a few times. Look inside the lock mortise for any rub spots showing where the wood is binding on the moving lock parts.

It also sounds like you still may not have the right nipple. Get a Hot Shot or equivalent after-market nipple. GPR's have a strong spring so there's something else causing your problems. I've never ever had a misfire with my cap GPR after hundreds of rounds.

 

[necchi]

"I would check to determine if there is wood inside the lock mortise that is slowing down the hammer fall."

Good Point! :thumbsup:
A person can overtighten the lock plate screw too, (the one that holds the lock plate in the gun) and pull parts of the lock into the inside of the mortice. Carefull to leave the gorilla out of the equasion here.

 

[F_Thomas]

It is strange to me because it just started happening. In the past there was no issue. I'm not sure what that would tell us, but it had not been a problem at all. Then this last week at the range. Problems!

I have a 54 cal percusssion Lyman pistol and changing the nipple fixed it. It didn't fix it on the rifle. I did change the nipple.

 

[StewartLeach]

Sounds like something changed. Beyond what others have suggested, try these:

Is your lock bolt too tight? A too tight lock bolt can lead to internals dragging on wood, and to misalignment of hammer nose and nipple. Loosen bolt, then tighten just enough to hold lock in place. The bolt doesn't have to be tight- the lock is supported by the wood.

Is the nose of the hammer dirty? Build up of crud can cushion the hammer blow. Scrape it out.

I have a well developed routine for using my Tedd Cash Rifleman's Capper, the one that is lozenge shaped. After placing the cap, I flip the capper over and use the back to press the cap home firmly.

White Fox

 

[CoyoteJoe]

If it just started after you changed the nipple then most likely that is where the problem lies. Perhaps the new nipple is a bit shorter or longer of perhaps the caps are too tight on the nipple and the first strike just seats the cap and the second strike fires it. Check to be sure the hammer nose recess is not dragging on the side of the cap.

 

[F_Thomas]

Thanks guys! White Fox and yourself brought up a few things that I had not thought of entirely. The hammer is almost spotless. OK, I'm going to try a few caps and I will be back in a bit.

 

[rafterob]

Had the same issue with a CVA and went through everything I could think of. Then I finally compared the new nipple to the old one and it was a tad shorter so the hammer did not strike it fully.

 

[F_Thomas]

IT IS NOW FIXED! :thumbsup: :thumbsup: Whatever combination of things that I did fixed it. So, thank you all for your input. I was helped by every single one of you to learn something. THANKS!!!!

 

[GP1951]

OK guys, I have changed the nipple and then reworked it with a file and I am getting hammer strike and no bang. Is this caused by something out of adjustment or is the spring weak?

It is ruining my target fun!!! Don't want to take it hunting until the problem is resolved.

I thought that I had worn a nipple out. Guess not!

If that is the factory Lyman nipple, it is best to just replace it with a new nipple from TOTW. That will fix the problem for sure. Some folks like the Ampco bronze, but I have no problems with the stainless steel for $3.99 each.

 

[tiger955]

I was browsing around online looking for some spares lately and came across those bronze nipples and was wondering about them. I am thinking that stainless is a harder, stronger metal and would be less likely to wear or break as fast as bronze.
As I understand bronze is an alloy of brass, which is pretty soft, or am I confused here?
Has anyone used these nipples? How do they hold up? Perhaps I should buy some and do a whole bunch of shooting to see how they hold up. Anybody got a good deal on Goex, I may need a few cases for my test.

 

[zampilot]

Try the stainless nipples.

 

[CoyoteJoe]

Over the 50 years I've shot muzzleloaders I've used Ampco, stainless and blued steel nipples. The blued carbon steel is the least subject to battering, they are so hard a file just skates off, but they are the most subject to burn out and rust out. Between stainless and Ampco bronze I don't see much difference in battering but I think the stainless will burn out faster. Also the stainless stands out like a sore thumb, especially on revolvers, where as the Ampco quickly takes on a dark patina which blends in with the rest of the gun. :grin: