Flintlock weirdness

[The other DWS]

The safety thread reminded me of something I saw years ago that I have never understood.  Maybe the collective wisdom might 'splain it to me.
  Back in the '70s I was into Rev and F&I war reenacting.   We had one "private" event where we were able to do a lot of live fire target shooting.  One of my friends had a real nice jaeger rifle with the usual reenactor's brass flash guard on it.  I don't recall who made it, but I know it was big bore and that he had in vested in a lot of stuff, including guns from Kit Ravenshear.  It was a real accurate rifle.
We were shooting prone on the 100 yard range.  He was a couple positions to the right of me.  we were all banging away happily and all of a sudden I heard an ungodly HI-S-S-S-S-S-S like the worlds biggest snake and all the shooting stopped.

His rifle vented the whole powder charge out the vent!!!  no bang, no ball down range.  After a nice long worrysome safety period the patched ball was checked it was still seated at normal depth for the powder charge.  Using a screw ball puller the ball and patch were pulled with no undue effort.  I don't know what he as using for lube on his patches.  other than being scorched the patch looked normal for a pulled unfired patch.   The rifle was VERY carefully inspected.  Including pulling the breechplug in the event host's shop.  Other than an moderately eroded vent and flash guard (and the need for a change of linen for the shooter and the guy to his right on the line) there was no damage.   Conditions were very hot and humid, we had severe thunderstorms later in the day.

Any idea what could cause some thing like this?  I asked Pa Keeler later that summer when I went up Eaton Rapids to pick up the powder for the event I was hosting.  He did not know but said he knew of a couple similar occurrences at Friendship over the years.

[bob in the woods]

Wet charge...didn't build up enough pressure to move the ball much or at all. The slow burn rate allowed the pressure to vent rather than build significantly. It's physics . 

[The other DWS]

so, damp enough to burn slowly from the back,  but too wet to ignite explosively eh?  makes sense.    caused by???   maybe a sloppy wet patch allowed to sit for a while before shooting---and several days of high humidity---we were also doing a lot of loading from paper cartridges of powder.  simple rolled and pasted paper tubes filled with premeasured powder charges, kept in our cartridge cases, rather than horns, so humidity could have gotten to it that way.    kind of a 'perfect storm' situation.

[Bob Roller]

The powder said GO and the ball said NO so the thing vented thru the touch hole. Sounds like sorry powder to me.I have seen home made black do this years ago. We had a kid in our neighborhood tjat was always messing around with home made pyrotechnics and made some that hissed like this when confined.
He also cooked up something that flashed bright white and glazed the concrete it was ignited on.

Bob Roller

[Scott Bumpus]

I had a similar event years ago.  Took my 45 cal flinter out hunting.  It rained all day on us and I joked to my partner at the end of the day that it would amaze me if my rifle would fire.  Put a fresh prime in the pan and touched it off,  had a roman candle effect hissing out the vent for about 5 seconds then  a dull woof and the ball came out going about 10 feet.  I learned to do better at keeping my powder dry after that. 

[doug]

    I had a gun do something vaguely similar many years ago.  We were shooting a trail and I was both guiding and shooting.  The target was shot with powder from a small measure (about 15 grains or so) and the others in the group were asking me endless questions (how far is the next shot and so forth).  I forgot and left the ramrod down the barrel.   I shot and the ramrod came zinging out, hit a stump and broke.  The gun hissed for a surprisingly long time (probably only 2 or 3 seconds).  The rest of the group stood with their mouths open and long after it would have done any good, jumped back.  I thought of tossing the gun but figured it would have blown right away if it was going to, so hung on to it.

     The ball wedged around the brass ramrod tip about 1 foot from the muzzle and I had to literally hammer it down to the breach so that I could shoot it out.  To my good fortune the bore was undamaged and  I shot the gun for another 20 or 25 years.

cheers Doug

[Dphariss]

Ditto the damp charge.

Dan

[omark]

several yrs ago i was target shooting and had the now famous "hiss", then a boom as the ball exited at a high rate of speed. it eroded the vent a little. and the charge was not wet. i dont go out to shoot by myself in the rain.       mark

[northmn]

Wet powder, too light a charge and oversized vents can all add to that cause.  I used to make a little extra change installing vents on commercial rifles.  One was a 45 that had a vent that must have been at least 3/32 inch.  The individual using it wanted to shoot about 25 grains up close.  It would do that on occasion.  He had me install a stainless vent.

DP

[Daryl]

Possibly a bad 'chunk of pyrodex - too-large a vent - wet powder, due to water left in the breech area or vent cone after wiping the barrel.