Patent Breech construction

[Bill*B]

I ran an endoscope down the barrel of my little Thompson Center White Mountain Carbine, and was surprised to see what appears to be a threaded bolt running across the patent breech, just behind the opening of the flash channel. Is this how these rifles were made? I had imagined that the patent breech would end in a smooth cup.

[pietro]

.

This is a cross section view of a T/C Hawken patent breech (the WMC breech appears to be identical)

https://i.imgur.com/FjVFrCx.jpg

[Bill*B]

Thank you. This was my first experience with the endoscope - short focal length lenses take a little getting used to - I think I was seeing tool marks, and misinterpreting them.

[indian joe]

picture explains why I like nipple drum ignition better !

[megasupermagnum]

picture explains why I like nipple drum ignition better !

Say what you will, but there is nothing wrong with TC's patent breech plug. Sure, the TC uses two 45 degree angles verses one 90 degree turn, but you don't hear about the TC plugs blowing out of rifles either. No matter how you slice it, a drum was nothing but a cheap solution to convert a flintlock to a percussion cap, and it works.

[waksupi]

Say what you will, but there is nothing wrong with TC's patent breech plug. Sure, the TC uses two 45 degree angles verses one 90 degree turn, but you don't hear about the TC plugs blowing out of rifles either. No matter how you slice it, a drum was nothing but a cheap solution to convert a flintlock to a percussion cap, and it works.

They are much harder to clean properly.

[megasupermagnum]

They are much harder to clean properly.

No, they aren't. I've used both, and there is nothing wrong with the TC breech plug. Water cleans out both with no problem.

[centershot]

+1 to what MSM said! I've shot a number of TC rifles over the years, no problem at all to clean!

[dondiego]

You have to be sure to flush a good amount through the breech though. It is definitely easier to clean a normal breech with surety.

[frogleg]

Pietro thanks for the picture that’s definitely worth a thousand Words
I pull the nipple and put that end in a coffee can of water and pump a cleaning patch up and down the bore. I see why that cleans it so well by the picture.

[indian joe]

I was looking at the length of the skinny ignition channel, 2X what a nipple drum has = 2 x the potential to get a problem with bridged powder and a misfire -
The closer the source of ignition is to the main charge the more reliable ignition will be (other things being equal) applies to flinters too.................

I dont like sidehammer and underhammer guns but (regardless of my personal likes/dislikes) those things can have super fast ignition

[rfd]

They are much harder to clean properly.

Spot on. I hate patent plugs, what a pain mostly for fouling control, but also final cleaning. Requires a patched brush to get into the smaller ante-chamber, after cleaning the bore (which pushes more crud in the patent breech). I've never seen a performance advantage for any patent breech plug, cap or flint, just more effort and tools to lug around. And 99% of all offshore sidelocks sport those buggers. Ack. More power to those who love 'em, YMMV.

https://i.imgur.com/Bm0j02b.jpg