Cap Fragmentation

A silly question, perhaps, but what causes a cap to fragment after ignition? Is it caused by the tiny flare of the fulmunating compound in the cap, or by blow-back though the nipple as the powder goes off?

I've never had a mis-fire yet, but if I do, I'm wondering how hard it will be to get the cap off the nipple. I shoot an 1860 Colt, and it "sheds" the split caps neatly as I progress through the cylinder.

 

[roundball]

Those things probably contribute to the cap splitting...and the hot shot nipples with the tiny hole drilled into the side of the nipple where the cap sits really blows them open!

If get one gets stuck on a nipple of a sidelock, there's a apecial tool to remove them but that's just another thing to carry...all you have to do is use your knife blade to catch the edge of it and slide it / peel it right up off the nipple.
Don't know what to tell you about the revolver...

 

[Zonie]

Use the same method Roundball gave. Just take your knife (a pocket knife with a pointed blade works best) and pri the cap off of the nipple.
Of course you should be wearing shooting glasses at all times while shooting but if your removing a unfired cap it becomes even more important.
During prying a unfired cap can go off and while it really wont hurt your fingers (much) it can be devastating to an eye.

 

[musketman]

Another reason cap fragment after ignition could be the way they are designed.

First: They are made of a soft thin copper...

Second: They may be scored on the inside to assist fragmentation...
see link: http://www.researchpress.co.uk/firearms/caps.htm

Third: They just got slammed by a big, hard steel hammer...

Last: The explosion of the fulminate and the blow back of the main charge.

 

[Aline]

I don

 

I thought of "cap-firing" after I posted -- sort of: "Duh -- why don't you just fire a cap and see?"

I've not cap-fired before loading myself, because, with a revolver (or at least with this one), it's just as easy to hold the cylinder up to the light, turn it, and see if the nipples are occluded.

 

[45man]

Morrisey, I shoot Rem caps, or CCI's with no trouble. They fall away without sending pieces back at me. I have never been hit with a particle from them. Then someone got me 1000 RWS caps cheap. They scare me. I have picked pieces out of my nose and cheeks, lots of blood! I even scarred my shooting glasses. I will not shoot them again. I use them to clear nipples by holding the guns upside down and low. I can feel pieces hitting my pants and boots. The metal they are made from is very brittle.

 

[musketman]

The metal they are made from is very brittle.

The priming mixture may be a little too much for the caps, +pressure caps?

 

[Zonie]

I would suggest saving your RWS caps for your rifle.
Most rifles have a pocket in the hammer face thus they create a shield around the cap which will prevent the fragments from hitting you (most of the time).
IMO RWS does make rather hot firing caps which work well in rifles.

 

[musketman]

They also make a FLASH CUP for percussion rifles, they work like the flint FLASH GUARD version...

http://www.cabelas.com/information/HuntingOptics/FlashGuard.html

A little extra insurance in a fulminate world...

 

[Zonie]

I've tried the flash cups and didn't really like them.
They are installed under the nipple so they raise it about 1/16 of an inch which keeps the hammer from hitting squarely. They also make removing a "dud" cap more difficult because it is down inside the cup.
As far as fragmentation is concerned, they tend to blow the vented powder gas back up towards the shooter. I never had any cap fragments hit me (that I know of) but IMO it increases the likelyhood of it happening.
The only thing the flash cups did was to keep the lock and the stock nice and clean.
I don't use them anymore.

 

[BrownBear]

I have a bad habit with caplock rifles, left over from years of formal target shooting- I shift my forward hand all the way back and rest the trigger guard on my thumb and the forend on my fingertips so I can lock my elbow back into my side. It's a real downside for shooting right handed muzzleloaders left handed, and I haven't met a cap yet that didn't blast my wrist with burning compound and/or cap fragments.

Any time I can remember it I wear a shooting glove, but there is a growing collection of burn holes in the cuff of my favorite shirt. Kinda wondering what's going to happen when I get a big cup fragment, but so far they have been small enough not to penetrate my wrist too far- I can pluck them with good tweezers. The cup sounds like a good idea till I start thinking about taking the tweezers to my forehead!

 

BrownBear,.... Ya might haft'a change over ta flintlocks!! :haha: :haha: ::

 

[Zonie]

BrownBear: Don't let my comments and speculation deswade you. As I indicated, I don't really recall getting hit by any fragments. I basically just didn't see any value for me and the way I shoot.
Actually you sound like a prime canadate for using one of these cups. They don't cost much so even if you don't like it, you haven't lost much.
Give one a try. It definitly will keep the chunks of cap fragments out of your sleeve.

 

[BrownBear]

So much to learn. So little time.