Nipple testing

[kh54]

Greetings All. A couple of weeks ago I posted a thread about some unusual nipples on an early Italian 1st model Dragoon that I have with a 1976 proof date but no manufacturer's marks. (See 56e953a9-e418-4b38-a4f1-d96c88c06fff-jpeg.138864 (710×800) (muzzleloadingforum.com) I'm starting a new post because what I recently tested also included an Uberti 1849 pocket .31, 2003 proof date.

Like many others I've had some frustration with numerous cap jams, especially with my Colts - not so much with the Remingtons. I think my jams fall into two categories:

1. There are caps that do not easily fall off the nipple when the next chamber (or two) is rotated into position to fire. Sometime those snag between the cylinder and frame near the hammer and sometimes I forget to look and rotate them too far, such that they snag in the frame near the loading lever.​

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2. Some caps or fragments drop into the frame in front of the hammer and jam the hammer. Sometimes fragments even make their way into the action below the hammer.​

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The first fault I had most recently with an Uberti 1st model Dragoon, and the second problem most recently with an Uberti 1849 pocket revolver.

Some time ago I tried Slixshot nipples on an Uberti 1851 Navy but I didn't see much improvement. It certainly wasn't enough to warrant preplacing nipples on something like 25 revolvers (25 x $39.00 = $975!!) I can live with a few cap jams for that much cheese or just use the same nipples and move them from gun to gun, depending on what I feel like shooting on a given trip to the range.

After posting about the unusual nipples that are on the unmarked 1976 Dragoon, I tried them yesterday in the Uberti 1st model Dragoon. (Screw threads are the same.) I also tried the Slixshot nipples that I originally put in the 1851 Navy in the 1849 pocket. I have attached a photo of ten spent caps from the Dragoon (top two rows) and four spent caps from the pocket (bottom row). I didn't think to first try and save spent caps from the stock nipples before swapping out the nipples, but they are often too mangled from getting caught in the gun to show much. I used 40 grains 3F powder, no wad, both round and conical balls in the Dragoon; 10 grains 3F, no wad, round ball only in the pocket revolver.

The unusual nipple design on the Dragoon worked much better than the stock nipples. You can see that the nipples were sufficiently blown apart that they easily fell off when I cocked the gun for the next round. I had two or three jam slightly but they either fell off with the second cocking of the gun or I shook them off. You can also see clearly where the cap was deformed by the notch in the hammer. I've read some claims that the notch will "suck" off the nipple, causing jams as described in (2) above, but this didn't happen with these nipples.

The Slixshot nipples worked much better on my 1849 pocket revolver than they did on the 1851 Navy, but I think this is key: I noticed that the stock nipples on the 1849 pocket seem to have too large a vent hole and I'm convinced that's what was causing blowback and dropping caps or fragments into the frame, NOT the "sucking" action of the hammer notch. The vent hole on the Slixshot nipples is just slightly smaller, but I don't think there was any hammer blowback. The caps rotated with the cylinder with the next round and fell off like they're supposed to, rather than falling in front of the hammer and causing a jam. Especially on the third cap from the left on the bottom row you can see the imprint of the hammer notch, but none of these were pulled off the nipple by the hammer.

I wrote in someone else's thread recently that I wasn't impressed with the Slixshot nipples, but that was my experience with the 1851 Navy. They worked well in the 1849, but I think that is primarily due to the smaller vent hole. I want to experiment more.

All in all I would call this experiment a success. I may next try to modify a set of nipples on a .44 or .36 revolver to mimic the nipples that were on the unnamed Dragoon. A little work with a Dremel tool should work.

What do y'all think?

 

[golden sky]

i would chuck up those nipples in a small lathe , and clean em up with a carbide cutter, true up the face of the nip, anyone try adding a 45* chamfer to the inside face of the nipple, try to maximize gas flow into the chamber..?

is that smooshed nipple designed to be that way?

 

[necchi]

Interesting study, A Thank's up-front for sharing.
The "unusual" nipples obviously have a larger fire channel and seem to have been modified at some time.
But how does their "vent hole" as you mention compare to the others?
I only ask because you mentioned a noticed difference between the stock `49 nipples and the Slixshot used in same,,

The powder charge differences between calibers has to make direct comparison of nipple performance difficult, but your sharing of what works best is valuable to all.
Just pickin yer brain,, again Thank's for sharing,

 

[Uncle Miltie]

While you're modifying things might want to shorten the cones so the hammer just detonates the cap but does not touch an uncapped cone.

 

[TDM]

The notch cut in the hammer to catch the cylinder safety pins is responsible for a lot of cap jam problems.

 

[bang]

I find it helpful to give the pistol a quick twist right as it's cocked. Helps throw fragments out.

 

[Dude]

Can you measure the flash hole? I've heard that .024" is the best size for real black powder.

I'm trying to decide how to fill the hammer notch since I don't use the safety pins, and have heard the notch is responsible for the majority of cap jams. The best 'safety' is loading five and leaving the empty under the hammer. It seems like filling with solder should do it.

 

[kh54]

I haven’t measured the flash holes in any of mine. Use JB Weld to fill the hammer notch. It’s easy to file smooth and to remove later if you wish. (Heat will depolymerize the epoxy.)

 

[Dude]

Maybe I'll try epoxy.

You should get a box of small gauge pins. But you can order just a few to tell you what range you're in. Maybe in .005" increments .024 to .039" . I've got an almost new Uberti Walker with nipple orifices measuring .039". That's way too large! I'm looking into getting some beryllium copper rod to replace the channel, then drill to .024". That's a whole lot cheaper than getting slix shots or any of the aftermarket nipples. I can get 3 1/2 feet of beryllium copper rod for $20 - that'll line a lot of nipples.