Lack of a tight seal on nipple threads a likely cause of misfires?

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SomeDude

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I have been having some misfire issues with my Kentucky pistol since I got it last year and have just recently had time and access to a place to test it.

Because of the cap shortage I had to buy a musket nipple to replace the normal No. 11 one that came on the gun. It was causing the hammer not to hit the cap flush, but I fixed that with some washers.

Anyway fast forward to today it's still misfiring. The only way I can get it to reliably shoot is if the first few shots, I dump some powder down the screw hole into the breech. After it shoots a few times like that it seems to start working more than a few times with just the caps, but eventually always begins misfiring again before long.

Well today when I cleaned it I finally noticed that the seal created by the threads on the nipple doesn't seem too tight. I was drawing in some hot and soapy water with a patch and rod, and forcing it back out to clean, when I accidentally lifted the breech above the water line and could see a pretty hefty jet of water shooting out of the breech past the nipple's threads. If that's not enough evidence of a lousy seal there, I have also always noticed that there's always powder burns on the side of the gun from the caps, but I had chalked that up as normal.

Now, I am just assuming this must be the problem at this point, or at least one more thing to try. Seems the only logical thing it could be. My guess is that the explosion from the cap loses pressure by the time it gets through the breech and so can't properly ignite the powder in the barrel. My other guess is that loading the breech with powder just manages to let the nipple ignite the powder via a shorter distance, and that then the more energetic ignition of the powder in the breech finally reaches the powder in the barrel with enough pressure and heat.

Well theories are fine and everything but how can I make sure there's a good seal on the nipple's threads? I thought about plumbers tape, but I am not sure if it's meant for threads that fine or if the temperatures would be too hot for it. Otherwise I thought about putting some flux on the threads and dropping a little solder down there but that seems like an extreme measure. Maybe wax could accomplish the same thing.
 
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Did you put washers between the musket cap nipple and the breech? There really aren't a lot of threads on a nipple and you shouldn't reduce the thread engagement by much, 1 washer max. Your cleaning procedure is good but could you repeat the test without the washers and then again with the original #11 nipple? That might tell you if the threads in the bolster are damaged or if your new nipple is at fault. BTW, it's the sides of the threads and not the top and bottom that make the seal. Is it possible that the musket cap nipple is a different but close thread? That can happen. If the threads on the new nipple are correct and it is installed correctly there should be no leakage baring damage to the bolster threads. All too often nipples are way overtightened which can damage both threads, snug is good enough. Teflon tape works more as an anti-seize on the threads than a sealant and it holds up fine when used on nipples so long as you don't accidentally allow it to cover the end of the nipple. Solder will likely cause more problems than it will cure. I wonder if the leakage and the misfiring aren't 2 separate issues, there are nipples on the market that have holes drilled in the side and they work fine, a lot of shooters swear by them.
 

rafterob

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It would be good to know what Kentucky pistol you have. Loose threads allowing gas leakage and extra air in that space could cause excessive fouling in the flash channel. That would cause your misfire issue. Using washers to shim out the nipple as pointed out byHawkeye2 is probably not a good idea. You may need to seek other remedies such as trying to find a musket nipple that fits your threads and has a longer neck. I have a CVA Mountain Pistol that had minimal threads in the bolster and they were boogered up at that. That nipple blew out on me so I retapped to a larger size and all is good now.
 

flntlokr

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I would think that a gas leak past the nipple threads indicates mis-threading, either because of unmatched threads or cross-threading. If you persist in shooting it that way you run a risk of burning the threads out and blowing the nipple. You shouldn't need a musket cap to light up a pistol. I swould be looking at the flash channel into the barrel from the nipple onwards. You may have a persistant fouling build-up possibly caused by oil residues from cleaning that is constricting the flash channel resulting in excess pressure blowing back and blocking the spark.
 
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SomeDude

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Did you put washers between the musket cap nipple and the breech? There really aren't a lot of threads on a nipple and you shouldn't reduce the thread engagement by much, 1 washer max. Your cleaning procedure is good but could you repeat the test without the washers and then again with the original #11 nipple? That might tell you if the threads in the bolster are damaged or if your new nipple is at fault. BTW, it's the sides of the threads and not the top and bottom that make the seal. Is it possible that the musket cap nipple is a different but close thread? That can happen. If the threads on the new nipple are correct and it is installed correctly there should be no leakage baring damage to the bolster threads. All too often nipples are way overtightened which can damage both threads, snug is good enough. Teflon tape works more as an anti-seize on the threads than a sealant and it holds up fine when used on nipples so long as you don't accidentally allow it to cover the end of the nipple. Solder will likely cause more problems than it will cure. I wonder if the leakage and the misfiring aren't 2 separate issues, there are nipples on the market that have holes drilled in the side and they work fine, a lot of shooters swear by them.
Oh, no the washer is where the hammer meets the lock. It was a little too far over to the left and making the raised edges of the hammer clip the edge of the cap. It's hitting flush now.

Good idea on checking for the same leak with the original nipple. Both are supposed to be the same thread size--M6x1 if I remember right. But if course not everything is always machined equally. I do notice that it's kind hard to get the threads started

It would be good to know what Kentucky pistol you have. Loose threads allowing gas leakage and extra air in that space could cause excessive fouling in the flash channel. That would cause your misfire issue. Using washers to shim out the nipple as pointed out byHawkeye2 is probably not a good idea. You may need to seek other remedies such as trying to find a musket nipple that fits your threads and has a longer neck. I have a CVA Mountain Pistol that had minimal threads in the bolster and they were boogered up at that. That nipple blew out on me so I retapped to a larger size and all is good now.
It's a Traditions .50 caliber. Made sure there's not any oil left in there and I can shine a light down the barrel and see clear through into the breech before loading and firing.

Here's some pics

As it's screwed into the gun and versus with the original No. 11 nipple it came with.
PXL_20220603_003400154.jpg
PXL_20220603_003656618.jpg
 

flconch53

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I would also look at the drum. If it leaks with your other nipples just replace the drum. Traditions also uses a flash chamber that can get clogged up. Your cleaning procedure should avoid this . You Haven't said Black or substitute. Wax won't work. If there is a leak the back pressure would blow the wax out. The 1st thing to determine is if it is the nipple or the drum. Did you buy the gun new?
 

smoothshooter

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I have been having some misfire issues with my Kentucky pistol since I got it last year and have just recently had time and access to a place to test it.

Because of the cap shortage I had to buy a musket nipple to replace the normal No. 11 one that came on the gun. It was causing the hammer not to hit the cap flush, but I fixed that with some washers.

Anyway fast forward to today it's still misfiring. The only way I can get it to reliably shoot is if the first few shots, I dump some powder down the screw hole into the breech. After it shoots a few times like that it seems to start working more than a few times with just the caps, but eventually always begins misfiring again before long.

Well today when I cleaned it I finally noticed that the seal created by the threads on the nipple doesn't seem too tight. I was drawing in some hot and soapy water with a patch and rod, and forcing it back out to clean, when I accidentally lifted the breech above the water line and could see a pretty hefty jet of water shooting out of the breech past the nipple's threads. If that's not enough evidence of a lousy seal there, I have also always noticed that there's always powder burns on the side of the gun from the caps, but I had chalked that up as normal.

Now, I am just assuming this must be the problem at this point, or at least one more thing to try. Seems the only logical thing it could be. My guess is that the explosion from the cap loses pressure by the time it gets through the breech and so can't properly ignite the powder in the barrel. My other guess is that loading the breech with powder just manages to let the nipple ignite the powder via a shorter distance, and that then the more energetic ignition of the powder in the breech finally reaches the powder in the barrel with enough pressure and heat.

Well theories are fine and everything but how can I make sure there's a good seal on the nipple's threads? I thought about plumbers tape, but I am not sure if it's meant for threads that fine or if the temperatures would be too hot for it. Otherwise I thought about putting some flux on the threads and dropping a little solder down there but that seems like an extreme measure. Maybe wax could accomplish the same thing.

Is it possible the nipple seat has metric threads and the nipple has standard threads, or vice-versa?
If they are a close match, but not exact, it would fail to seal up correctly.
 

SomeDude

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I would also look at the drum. If it leaks with your other nipples just replace the drum. Traditions also uses a flash chamber that can get clogged up. Your cleaning procedure should avoid this . You Haven't said Black or substitute. Wax won't work. If there is a leak the back pressure would blow the wax out. The 1st thing to determine is if it is the nipple or the drum. Did you buy the gun new?
Which part is the drum? Is that what the nipple is screwing into?

I'm using Pyrodex RS which is 2f I believe. It's all I could find but I was assured by a few people that it would still work fine in a Kentucky pistol vs a ball and cap revolver. But I have been wondering about that assurance.
Who's musket caps are you using? CCI musket caps do not have a good reputation for reliability.
Yep the CCI ones. I didn't really think about it being the caps since they detonate every time, just don't seem to ignite the powder reliably.
Is it possible the nipple seat has metric threads and the nipple has standard threads, or vice-versa?
If they are a close match, but not exact, it would fail to seal up correctly.
I don't think that's the case since it's a Traditions pistol and a Traditions nipple and I know they're made in Spain, so I'm pretty sure it's all metric.
 
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Which part is the drum? Is that what the nipple is screwing into?

I'm using Pyrodex RS which is 2f I believe. It's all I could find but I was assured by a few people that it would still work fine in a Kentucky pistol vs a ball and cap revolver. But I have been wondering about that assurance.

Yep the CCI ones. I didn't really think about it being the caps since they detonate every time, just don't seem to ignite the powder reliably.

I don't think that's the case since it's a Traditions pistol and a Traditions nipple and I know they're made in Spain, so I'm pretty sure it's all metric.
The nipple is threaded into the drum.

Pyrodex is notoriously difficult to ignite. This is especially true when you have all the turns from the nipple through the drum and making a turn into the reduced diameter chamber in the breech. Then you have the less hot CCI musket caps. They work to fire the charge for some people, but not everyone.

You may have an accumulation of dried oil in the path from the nipple to the powder chamber. Clean that flash channel with rubbing alcohol using a pipe cleaner.
 

bang

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Is the base of the musket nipple all the way down on the drum?
Is the thread journal length correct?
Metric and sae mix up.
 

SomeDude

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The nipple is threaded into the drum.

Pyrodex is notoriously difficult to ignite. This is especially true when you have all the turns from the nipple through the drum and making a turn into the reduced diameter chamber in the breech. Then you have the less hot CCI musket caps. They work to fire the charge for some people, but not everyone.

You may have an accumulation of dried oil in the path from the nipple to the powder chamber. Clean that flash channel with rubbing alcohol using a pipe cleaner.
Hmm yeah and I still have never managed to find any 3f Pyrodex or No. 11 caps (or musket caps aside from CCI) to compare with so I have been trying to wait until the supply of that stuff is back to regular.
Is the base of the musket nipple all the way down on the drum?
Is the thread journal length correct?
Metric and sae mix up.
Yeah there's a small gap where the drum and the base of the nipple meet, but only because the drum is radiused. Otherwise the base is touching the drum. As far as I can tell with my calipers the diameter, pitch and the length of the threads are all identical to the stock No. 11 one that came with the gun.
 

flntlokr

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Which part is the drum? Is that what the nipple is screwing into?

I'm using Pyrodex RS which is 2f I believe. It's all I could find but I was assured by a few people that it would still work fine in a Kentucky pistol vs a ball and cap revolver. But I have been wondering about that assurance.

Yep the CCI ones. I didn't really think about it being the caps since they detonate every time, just don't seem to ignite the powder reliably.

I don't think that's the case since it's a Traditions pistol and a Traditions nipple and I know they're made in Spain, so I'm pretty sure it's all metric.
I think the pyrodex may be a big part of your problem. When I tried it in my CVA Kentucky, it lit up reliably (311cap), but didn't build enough pressure to give the ball any velocity, and I could hear the last of the powder cooking off in the barrel after each shot. You might try putting 5 gr or so of black in before the pyro in order to light it up faster, but if the ball gets out of the barrel too soon, there willnot be enough time for the pressure to crank up, and the ball will ore or less dribble out.
 
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That stainless nipple looks like it has a smaller hole at the base than the blued one. Also, is the length of the nipple, where the threads are, the same as the other? If it's longer, maybe that is affecting the shark's travel into the chamber, or it's bottoming out inside the flash channel before it seats properly.
 
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