Curing a cap-sucking C&B with new nipples


PDA






duelist1954
January 14, 2013, 08:55 AM
I have a pair of 1851 Navy revolvers that were notorious for cap jams. One is an old Armi San Marcos made gun and the other is made by Pietta. I recently equipped them with aftermarket nipples made by Slix Shot. These nipples have a re-designed combustion chamber and two lateral vent holes in the cone. That relieves the back-pressure from the exploding charge of powder in the revolver's chamber. It cured the cap jams in these two guns.

https://www.youtube.com/watch?v=Hns_tEWBFD0

If you enjoyed reading about "Curing a cap-sucking C&B with new nipples" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
SleazyRider
January 14, 2013, 09:37 AM
Timing is everything, Duelist 1954, and yours is impeccable! I've been wrestling with my 1851 Pietta Sheriff's model for quite some time. It eats caps like pizza at a WeightWatcher's meeting, especially since I installed a reduced power spring. I love the reduced power for ease of thumb cocking and trigger pull, but it certainly has increased its appetite for caps tenfold. Yesterday I installed a full power spring, which helped considerably, but it's still not 100%.

So my next move was to pin the hammer slot and cut a corresponding groove in the face of the hammer, as well as dredge out the cap exit channel to the right of the hammer slot. But your suggestion to replace the nipples with Slix Shots seems a whole lot easier. Maybe I can even go back to my beloved reduced power spring. So thank you for your timely post and video!

Hellgate
January 15, 2013, 07:00 PM
Sleazy,
Before you go mangling your hammer and pinning the frame. Just fill in the safety notch with JB Weld or better yet brazing or welding it shut. What happens is when the gun is fired the cap is getting grabbed by the notch and is being pulled off the nipple where it gets knocked off the hammer by the frame when you cock it so it falls into the hammer cutout. Also your light spring is letting the hammer blow back and the cap can get under the hammer and into the works. First thing to do is fill that notch and see if the problem persists. If so, get the Slix-Shot nipples which will prevent blowback. The designers of the Sliz-Shot nipples use very light hammer springs and are shooting quite well with them (they beat me every time). I have moderately light mainsprings and do not have the jams I used to have once I came up with the notch fill idea. I think NOZ first mentioned the idea on a SASS Wire post and I wrote up the technique in the Cowboy Cronicle back in November 2009. I actually think the Slix-Shot boys also fill in their safety notches too but I am not 100% certain of that. I'll have to ask them at the next match. But please don't mangle your gun by drilling, pinning and ruining the hammer which would possibly didminish its value. Fill the notch and get the nipples first.

44 Dave
January 15, 2013, 10:07 PM
Just got my Slix-Shot nipples today.
I have a 1860 made by Ubirti in 1969 for Dixie Gun Works it has been doing the "cap crap" This old gun uses the "Pietta thread" 6x.75.
I was warned on this forum that the Pietta nipples may be too long. They were, I had to turn .010 off. They just cleared the frame with out caps and I wondered if the recoil could slam the cylinder hard enough to set an extra cap off.
I won't fill in the hammer notch as I use it and load all 6 when am shooting at my private range.
Won't get to shoot 'till Thursday but will report after test fireing.

Hellgate
January 15, 2013, 10:20 PM
44 Dave,
I have only owned Uberti Remingtons and they use the 12X28 nipples. I get it on not filling in the safety notch. I use all mine in CAS matches where we only shoot 5 rounds per gun. If I need to carry 6 I use a Remington that has the safety cutouts in the cylinders.

Smokin'Joe
January 16, 2013, 02:45 PM
The best of both worlds! A solid face hammer and a safety notch.

http://www.thehighroad.org/showthread.php?t=607779

http://www.thehighroad.org/showthread.php?t=633020

SleazyRider
January 16, 2013, 07:42 PM
Thanks, Hellgate, et al, for your concerns and input. I'll follow your sage advice and hold off. But the tinkerer in me wants to imitate the Slix Shots nipples by taking my existing nipples and very precisely drill the two vent holes and slightly enlarge the hole on the cap end, but only going down enough to intercept the vent holes without drilling through the entire nipple. I've got nothing to lose, since it's my intention to replace the nipples anyway. And, of course, filling in the notch with JB Weld is certainly an easy enough experiment. If it works, I'll grind it out and install a more permanent braze at a later date.

I bought this hundred-dollar Pietta just to tinker with, and foolin' with it has given me more pleasure than many of my big-ticket guns that need nothing. :)

Hellgate
January 17, 2013, 01:06 PM
Sleazy,
I have "dimpled" or beveled the tops of nipples to create a funnel shape to focus more of the cap's energy down the flash channel. That is an easy thing to do. sounds like you are doing one step better. There is a saying: "Italian cap & ball revolvers make gunsmiths of us all". I consider muyself an "advanced tinkerer".

SleazyRider
January 17, 2013, 03:43 PM
Just finished enlarging and venting my nipples a few hours ago, Hellgate, so I'll give you a range report in a day or so if I can break loose to go make some smoke. Fingers crossed!

44 Dave
January 18, 2013, 01:10 AM
First test fire of 1860 with Slix-Shot nipples.
I only fired 6 rounds with 27 gr of good old DuPont FFF. The Remington #10 caps still split but did not fall under the hammer.
The temp at the time was 6 degrees and I had not brought powder to reload.
Hope to shoot more next Monday.

BSA1
January 18, 2013, 11:54 AM
I keep coming up with dry holes trying to find a vendor that sells Tresco nipples. Anyone know of a source?

mykeal
January 18, 2013, 01:02 PM
I keep coming up with dry holes trying to find a vendor that sells Tresco nipples. Anyone know of a source?
How about the manufacturer?
http://www.houseofmuskets.com/

BTW, it's Treso.

unknwn
January 21, 2013, 11:56 AM
Thanks, Hellgate, et al, for your concerns and input. I'll follow your sage advice and hold off. But the tinkerer in me wants to imitate the Slix Shots nipples by taking my existing nipples and very precisely drill the two vent holes and slightly enlarge the hole on the cap end, but only going down enough to intercept the vent holes without drilling through the entire nipple. I've got nothing to lose, since it's my intention to replace the nipples anyway. And, of course, filling in the notch with JB Weld is certainly an easy enough experiment. If it works, I'll grind it out and install a more permanent braze at a later date.

I bought this hundred-dollar Pietta just to tinker with, and foolin' with it has given me more pleasure than many of my big-ticket guns that need nothing. :)
Please, let us know how the range test works out for you.

SleazyRider
January 24, 2013, 06:47 AM
Well, I'm pleased to report that my homemade "Slix Shot" (vented) nipples worked like a charm. The nipples held onto the caps like my wife holds onto her money, and I didn't experience a single cap jam or failure to fire in 18 consecutive shots. In fact, so confident was I that, in a moment of giddiness, I fanned the last 3 shots. :eek:

Here's what I surmise is happening: First, slightly enlarging the cone diameter to about half the depth of the nipple reduces the rim thickness of the nipple, thus providing more surface pressure from the hammer. This may enable one to use a much lighter mainspring without compromising reliable ignition. When the cap discharges, the hot gases are forced through the nipple thanks to seal created by the snug fit of the cap and pressure from the hammer. Second, when the chamber fires, the gases change direction and want to escape the nipple in reverse, pushing against the hammer and cap. In the case of a light mainspring, this can push the hammer back a bit and blow off the cap. The vent holes allow the gas to escape out the sides instead, and the cap remains put. This is only a theory based on my limited experience; I'd certainly be interested in what others have to say.

Big Al Mass
January 24, 2013, 04:42 PM
I was just about to ask if the results of the Slixshot nipples could be achieved by drilling holes in the stock nipples. Interesting how things work out. Anyway, what size bits did you use to do the drilling?

SleazyRider
January 24, 2013, 05:31 PM
I was just about to ask if the results of the Slixshot nipples could be achieved by drilling holes in the stock nipples. Interesting how things work out. Anyway, what size bits did you use to do the drilling?
I used a #38 (.101") bit to open up the nipple cone, to a depth of about half to length of the nipple. Then about halfway down the cone I used a #58 (.042") bit to drill the two vent holes. I figured---correctly, I hope---that the reduced power mainspring would allow me to remove material from the nipple without compromising its structure. I stayed clear of the hole that enters the chamber.
To chuck the nipples in the lathe, as well as to drill them on the milling machine, I chucked a short scrap of aluminum round stock, and drilled and tapped a M6 X .75 hole the same as in the cylinder. I then screwed the nipples into the chuck, enlarged them with the #58 bit, and took a light facing cut so they'd all be precisely the same length. While I was at it, I relieved the edges a bit with 320 grit Wet-or-Dry paper. I used the very same chuck to hold the nipples in the Acer mill, after indicating the faces of the vise for dead center. All of this can be accomplished at home with a drill press, but the head machinist at work was out with the flu last week and I took advantage of the occasion to steal into the shop and use "his" (actually Company) stuff. He'd blow a cork if he knew a clod like me was messin' with his machines!
You could achieve equally good results using a drill press, though I'd make a drilling jig out of a small scrap of square stock for accuracy and repeatability.

Big Al Mass
January 24, 2013, 06:15 PM
Thank you for the excellent explanation SleazyRider. While my workshop is pretty meager, I feel confident in getting the job done with the tools I have.

SleazyRider
January 24, 2013, 06:39 PM
What I lack in tools I oftentimes have to make up with inventiveness, and I'm thinkin' very similar results could be achieved by finding a #8 or perhaps a #10 steel nut that has roughly the same inner diameter as the cone's outer diameter, and drill out the threads in the sacrificial nut to accept the cone. The flat on the nut can then be acccurately centerpunched and carefully drilled with the #38 bit---even with a hand drill. The nipples can then be individually inserted into the nut, which becomes a drilling guide.

---Fred

Big Al Mass
January 24, 2013, 06:50 PM
I do have a vise and a hand-cranked drill (I have electric drills available, but I prefer the control afforded by the hand-cranked one). Looks like that is the way to go.

I will try it out as soon as I can.

Alex

Smokin'Joe
January 24, 2013, 09:24 PM
I drilled this with a drill bit mounted in a Dremel tool. Held the nipple with vice grips.

http://i1215.photobucket.com/albums/cc510/SmmokingJoe/IMG_0003-2.jpg

SleazyRider
January 24, 2013, 09:34 PM
Looks like you've got good hands, Smokin' Joe! Why, you can do brain surgery on me anytime!

Did the vent holes cure the problem for you, too?

Smokin'Joe
January 25, 2013, 12:24 AM
Brain surgery? No way! Just take two aspirin and call me in the morning.

As for the vent holes, I really didnít have a cap problem. I had performed other remedies that seemed to work pretty well. I made a solid face hammer that does a fine job. I also adjusted the hammer to nipple gap to about .002Ē. A strong main spring also helps. When I installed the vented nipple nothing really changed. So I only modified one nipple.

rodwha
January 25, 2013, 09:49 AM
Is it believed this would cure the cap eating problem of the '62 Colt Pocket models?

I really don't want to fill in the hammer and make it a 4 shooter...

Smokin'Joe
January 25, 2013, 12:35 PM
Adjusting the hammer to nipple gap is the first thing I would suggest you try. With the gun assembled hold the cylinder all the way forward with the hammer in the firing position. The hammer should not actually touch the nipple. There should be a very small gap between hammer and nipple, about .002Ē. If the hammer touches the nipple it should be adjusted until you get the desired results. I very carefully and slowly filed the hammer face with a diamond file to get this gap. I was able to do this with the gun assembled and the hammer at full cock on my 1860. Next eliminate all of the sharp edges on the hammer slot with a file or stone. This technique worked well on one of my open top 44 cal guns but Iím still having trouble with caps on my Wells Fargo. Iím still working the issue on that guy. Not sure what to expect on your 1862. Best of luck.

arcticap
January 25, 2013, 10:32 PM
edit

Smokin'Joe
January 26, 2013, 12:25 AM
I worked on the hammer because there is only one hammer. With each spare cylinder the nipple count keeps increasing. But the important thing is the hammer to nipple gap. How you achieve that is unimportant.

Take a look at Pettiforgger's Tuning the Pietta Cap & Ball Part 2 http://www.theopenrange.net/articles/Tuning_the_Pietta_Part_Two.pdf and go to Page 20. He states "Remove material from the nose of the hammer until it no longer contacts the nipples".

If you enjoyed reading about "Curing a cap-sucking C&B with new nipples" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!