First build /underhammer .. nipple size problem

[ylhatch]

I have been reading the pages of this group for quite a while. You have been helpfull to guide me towards an underhammer.40 cal.I got the parts together and I have an un tapped hole for the nipple.The ipples that were recomended are quite long. 3/8" 14x28 Underhammer nipple from TOTW.They seem long. The hole on the inside of the nipple is deeper than Smaller diameter at the end of the nipple. So if I Cut the nipple . The hole
will be quite large. Does anyone know of a nipple that fits just right?? Maybe one that fits just so,where a patched jag would drag the end of it ever so briskly?Its 40 cal GM 13/16 .

 

[Zonie]

Your barrel size and caliber result in a thread length of your nipple that should be .206 long.

I just measured several standard rifle nipples sized for #11 caps and their threads were almost exactly this length.

The larger hole in the nipple at the mouth is designed to direct most of the caps flame into the lower part of the nipple where it constricts to a smaller size.
This smaller diameter should not be larger than .030 and if it is .025 that's all the better.

The small size restricts the gas leak when the gun fires and this is more important with a underhammer than with a common traditional sidelock.

As the threads are longer than what you need if it were me, I would measure the depth of the large hole and subtract this from the overall length of the nipple.
If this large hole is shallow enough you could shorten the threads.
If you figure that shortening the threads enough to work in your barrel will remove all of the tiny hole and open up the larger one, you will need to buy another nipple.

 

[ylhatch]

Thats what i figured. I was wishing thnat maybe someone knows a size that fits best.I havent drilled the hole yet. I found a standard nipple from TOTW . Gonna return these for sure . If a standard nipple will fit. I may do that. Thanks for your time zonie. This is my first build . Although,it is one thing after another. I am really excited. It started with a 1858 REM A few years back
. I didnt even read about any long guns. Then one day the underhammer bug bit and now im hooked.
I gotta have the proper nipple though. GOTTA make some smoke>>

 

[gmww]

I've used standard nipples in my underhammers including the thicker 1 1/8" barrels. They work fine.

 

[ylhatch]

Well, thanks for tip. I ordered a few standard nipples from Track.

 

[ylhatch]

I ordered some standard nipples and my measurement says they will fit just like I want. Thanks for the tip.
Happy holidays to you all.