percussion caps ? Culprit

[54ball]

Multiple discharges in revolvers are rare but they do happen. Sometimes I think they happen and the shooter my not be aware of it. Kind of like, did I fire 5 or six? Most of these incidents can be explained away by poor loading techniques but a good many cannot.
THEORY
Some multiple discharges originate from the rear "cap side" of the cylinder.

If this is so. It would seem impossible for the spark of an adjacent cap to pass through the next cylinder sealed by a percussion cap. Almost as impossible as fire from the front of the cylinder crossing through grease lead and wad from the front. The only way I could see a multiple discharge from the rear is that the percussion cap detonated on it own.
What would cause this. The only thing that comes to my mind is the shock wave from the adjacent cylinder. The shock wave moves through the metal and up the nipple. Depending on how the cap is positioned, shape of the cap charge, shape of the nipple ect. and if things are just so, the cap could detonate. Were talking microscopic tolerances here which would be impossible to correct or even see.

If this is so, It means that the percussion revolver is inherently dangerous and that in spite of great care a multiple discharge cannot always be prevented.
Since it is so rare an occurrence and most of the time the cylinder involved is in the clear I E fires down beside the barrel sometimes with the shooter not knowing it I would still consider the percussion revolver " handgun" as safe to shoot with care. A revolving rifle on the other hand is a totally different matter simply due to how it is held.

I love percussion revolvers and enjoy shooting them.
Any thoughts on this?

 

[Vtsmoker]

I too just can't understand the mechanics of how a multiple discharge happens. I know it can and does but can't see how :idunno: . Never had it or seen it happen and wonder if it does what kind of damage does it cause. Is it a catostrophic failure causing injury or just a "pop" that is barley noticed?

 

[54ball]

I've seen video of a civil war reenactor firing a 58 Remington. The side cylinder discharged at the same time as the main charge. The shooter did not notice.
Most multiple discharges seem involve the two adjacent cylinders which are in the clear. A real problem is when the bottom cylinder goes which is very rare.

 

[junkman_01]

I ,for one, am convinced that chain fires originate from the rear. I have had several in my career as a C&B revolver aficionado and none have been dangerous to the shooter, IF you hold the gun properly to begin with. Yes the recoil was much more than a normal shot but nothing that was overwhelming. The only danger that I see is to a bystander that is to the shooter's left or right, as the bottom ball will shatter and spit lead out to the sides when it contacts the rammer. Each time it has occurred to me, I was using #11 caps and had to pinch them (improper fit) when I should have been using #10 caps. I have never had a chain fire using Remington #10 caps on my guns. Proper fitting caps is the solution to avoid the dreaded chain fire!

 

[Greg Hardy]

I remember reading somewhere that Dance Brothers believed that the recoil shield on Colt revolvers were the cause of chain fires. It was believed that fragments from detonated caps were rebounding off of the recoil shield and actually firing off the adjacent chamber. Kinda makes sense, but...

 

[cowpoke1955]

I've been shooting C&B revolvers for over 30 years and fortunately, never had a chain fire. I use to use #11 caps and pinch them to make them fit snug. Under recoil, some times a cap or two would back off the nipples. I switched to #10 caps, which fit properly without pinching. I've always been careful to seal the front of the chambers. So, if a chain fire comes from the front or the nipple, I don't know :idunno: Maybe I'm just lucky :v

 

[jethro224]

In photos I've seen, almost the whole revolver appears engulfed in flame when fired. I wonder if sometimes enough heat or flame gets past those pinched caps at the loose spots to ignite the powder in the adjacent chamber(s). :idunno:

 

[Zonie]

When the gun fires a LOT of flame and powder gas exits thru the fired chambers nipple and the whole area is briefly aflame.

In the days of the pepperbox multiple firing was common and this led Colt to locate the nipple down in milled slots. He even patented the idea of having a fixed dam (if you will) between the chambers. The metal between the milled nipple pockets was his dam.

IMO, as long as the caps are seated tightly on their nipples there is little chance of a cross fire but more than once I've found that during firing an adjacent cap may pop off of its nipple.

This of course leaves an open vent hole for the flames at the rear of the cylinder that I mentioned before to flash directly into the adjacent chambers powder.

By the way, a cap can be jarred off of its nipple when a chamber fires and the flames at the rear of the cylinder take some time to clear the area.
If this happens the adjacent chamber can fire almost instantly.

 

[mykeal]

+1 Zonie.

It's not sparks that cause chain fires. It's the hot gas from the in-battery chamber reaching the powder in a nearby (and not necessarily adjacent) charged chamber. The only way something can take the path from one chamber to another through a small opening is if it's a gas. And the gas can get there from either the front or the rear. You need BOTH proper fitting caps AND balls.

 

[CaptainKirk]

+2 Zonie.

 

[Emet Huntsman]

Agreed. It's the hot gasses that are culprit. Sparks are too large to get through the areas mentioned, but hot gasses can penetrate even the tiniest openings.