Author Topic: Curious about percussion firing (Read 554 times)

Evil Dog · « **on:** March 13, 2005, 02:01:28 PM »

Most of the musket size nipples that I have seen would require a threaded hole of 5/16 x 20 or the like. Do you normally make the entire hole this diameter or just enough of it to do the threading and leave the remainder at around 1/8"? Is the nipple removed each time to brush the vent? Also most of the nipples that I have seen have a fairly small flash hole in the bottom of them.... is this normally left that way or opened up to 1/8" or so? If not opened up would require a pretty slim gimlet. I'm not seriously considering going to percussion at this time.... just curious.

Cat Whisperer · « **Reply #1 on:** March 13, 2005, 02:11:36 PM »

I have a stainless nipple for my .50 cal. TC. It's 1/4-28 threaded, for standard (smaller than musket size) caps and has a right-much small hole.

My point, the small hole is probably to limit the venting from the chamber when fired. Also, the distance it has to flame is short.

My plan in making a percussion device will be to have one that is readily removeable so the vent can be cleared after each shot and if needed charged. Since I have only steel tubes (and access to a few VERY strong neodimium (rare earth) magnets) you can guess how it'll be attached.

guardsgunner · « **Reply #2 on:** March 13, 2005, 03:08:10 PM »

There are a couple of options. Some of the original guns had a replacable vent which was made oversize, say on a 5/8" thread. It then had a small hole drilled through to the bore. ( to account for erosion )thread the nipple into the sleeve.
We drilled 3/32 through and counterbored the top leaving above option for a later date. We keep a 3/32" extra- long drill in the box just in case but have not needed to clean the vent even after 20 + rounds.
Friction primers send burning wax and 4fg powder down the vent. Various fuse leave behind their burnt remains. Caps and blanks send fire.
The bore sends fire back.
I dont know if the #11 cap (1/4 thread ) would have enough power for the larger guns.

Powder keg · « **Reply #3 on:** March 13, 2005, 03:17:46 PM »

Hey, I read some where, where a person was fitting his cannon to be fired by percussion cap. They had to drill out the hole at the bottom of the nipple to make it work. Isn't Calamity Janes cannon fired by percussion caps?

Cat Whisperer · « **Reply #4 on:** March 13, 2005, 03:21:44 PM »

Quote from: guardsgunner

.... I dont know if the #11 cap (1/4 thread ) would have enough power for the larger guns.....

I agree. That's why I'm building mine so it can be moved/removed easlily - to allow both cleaning and putting a little 4F into the vent.

Our 155mm howitzers use a primer that looks like an overgrown .410 shell (all brass) that shoots through about 10" into the red end of the powder bag (red end has a thin layer of blackpowder to catch the sparks).