Venting a percussion

[MuskratMike]

Recently I read an article touting the benefits of drilling out the clean out screw on the drum of percussion rifles to prevent misfires. Fact or fiction?

[Hungry Horse]

 There was a time when venting the drum on percussion guns was recommended in the back pages of the Dixie catalog. It alway seemed pretty dumb to make a percussion susceptible to rain, and humidity, which was the reasons many gave up flintlocks in the first place.

  Hungry Horse

[Dphariss]

There was a time when venting the drum on percussion guns was recommended in the back pages of the Dixie catalog. It alway seemed pretty dumb to make a percussion susceptible to rain, and humidity, which was the reasons many gave up flintlocks in the first place.

  Hungry Horse

Exactly. Dumb.
People find something on an old gun and never stop to think that some dufus had done it and it was a bad idea/failed experiment.

Dan

[little joe]

Has anyone tryed it?

[MuskratMike]

I am no expert but I believe the idea was to keep the vent hole clean to stop all the misfires. Unless hunting or shooting in a torrential downpour or holding your rifle with the lock up would much if any moisture get into the drum. I am not promoting this I just read an old article from the 60's and am asking if any old guys did it and if it helped.

[Daryl]

The platinum blow-out plug of English guns at their peak, 1850's through 1860's, had very tiny holes in the middle of them.
This is evident on Taylor's Joseph Lang rifle. After a few shots, there is a tiny smudge of PB fouling around the hole. I am not
sure of the reason (gun maker's thinking) for this hole. The actual hole is not as large as it appears in the photo.

[L. Akers]

When a percussion cap explodes the air in front of the flame-front is compressed.  If circumstances within the breechplug are right the compression of the air can be great enough to reject the flame and you get POP-no bang.  The idea of the vent hole is to give that pressure someplace to go, insuring the flame will reach the powder.  Platinum was used to prevent the hole eroding larger over time and is called a vent plug--not a blow-out plug because it won't.

[smokinbuck]

Mr Akers heard basically the same thing as me. The vent was used to allow air, and gases, in the flash channel to escape. I had a rifle years ago the I was unaware had a vent hole in the clean out screw. I found out when it burned the shooter next to me the same as a flintlock might have done.

[Pukka Bundook]

Good photo of a vent, Daryl.

According to Col Peter Hawker, when the percussion system was first employed, it was thought the pressure would be too high , as there was no touchhole to let some of the pressure out, so a vent was used to reduce pressure a little.
As these original vents were so small, rain entering was never a problem.
Some of mine have these vents, but most appear clogged .

The vent t was not a dumb idea, it was the product of logical thought.   The flint-gun had been in use for hundreds of years, and making a gun with no 'pressure valve"  seemed wrong.
This, plus  the fact that original Early caps were powerful enough to move the charge prior to proper ignition, and we can see the (logical) reasons behind the vent.

Best,
R.

PS,

Couple of mine.

[smallpatch]

The story continues with the vented “Hot Shot” nipples. They are vented though the side of the nipple.

[Daniel Coats]

I had a percussion long rifle once that had an air tight seal with the hammer down on a spent percussion cap. Pushing the next round down built up air pressure so when you released the ramrod it would shoot 15 feet in the air! Great fun showing off with that one which left bystanders in hysterics. The simple solution was to put the gun on half cock when reloading.

[Daryl]

Richard, that is the story I had heard & envisioned. Thanks for the notes on it. You would know for sure.

[Bob Roller]

I have drilled a few 8x32 screws years ago with a micro size drill for someone who
wanted to "vent" a caplock.I haven't thought of it until now.I have always loaded a
caplock at half cock so the compression of air can push the powder up to the base
and flash hole in the nipple.I think I still have those tiny drills and a neighbor gave
them to me.They were from a German shop and had the Hakenkreuz on the cylinder
they're kept in.
Bob Roller

[Daryl]

The story continues with the vented “Hot Shot” nipples. They are vented though the side of the nipple.

Dane, the explanation I recall on the hot-shot nipple venting near the top of the nipple tube, was to prevent cap fragments
by releasing excess pressure at that point so it would not blow fragments from the mostly coil spring locks on the market at
that time in the most popular production rifles of the day- mid 1970's. (CVA's and TC's)
My wife wore a tiny copper chip in her eyelid for 25 years due to a fragging cap from her Seneca. it finally worked it's way out,
but that small green piece of copper was there for a long time.

[Daryl]

I have always loaded a
caplock at half cock so the compression of air can push the powder up to the base
and flash hole in the nipple. 
Bob Roller

Exactly, Bob.

[Panzerschwein]

The story continues with the vented “Hot Shot” nipples. They are vented though the side of the nipple.

Dane, the explanation I recall on the hot-shot nipple venting near the top of the nipple tube, was to prevent cap fragments
by releasing excess pressure at that point so it would not blow fragments from the mostly coil spring locks on the market at
that time in the most popular production rifles of the day- mid 1970's. (CVA's and TC's)
My wife wore a tiny copper chip in her eyelid for 25 years due to a fragging cap from her Seneca. it finally worked it's way out,
but that small green piece of copper was there for a long time.

Yikes!

A pair of shootery spectacles finds its way in my pouch always, same from a pair of foam ear drum shielders.

[Daryl]

Yikes!

A pair of shootery spectacles finds its way in my pouch always, same from a pair of foam ear drum shielders.

Same here - she got that chip in about 1974. We've both worn shooting glasses since then.