magnum percussion caps

[hrt4me]

Under which circumstances, if ever, are magnum percussion caps called for and appropriate to use when firing black powder cap-and-ball revolvers?

 

[Grenadier1758]

I had one pistol designed for the hammer to strike the frame before it hit the nipple to allow for dry firing. There were some standard caps (CCI #11) that would not fire. The extra priming compound in the magnum caps raised the top of the ca enough for the hammer to strike the cap and fire. I have had some production revolvers that used #10 nipples that were a bit too short in the cone. They wouldn't reliably fire either and there is no such thing as a #10 magnum cap. There the choice was to buy new #11 sized nipples.

It is also appropriate to use magnum caps when firing a substitute black powder as you need a little hotter flame to ignite the substitute powers.

 

[Zonie]

IMO, the Magnum caps were made for the people who are using one of the synthetic black powders. These powders need a higher temperature to ignite.

With a revolver, the nipple directs the flame directly into the powder so most of the synthetic powders work just as good with regular caps.
In the case of a rifle, especially the ones that have a bolster mounted nipple, the long flame channel from the cap to the powder cools the cap's flame so these Magnum caps can make a difference in the rifles reliability. I might add that the German Dynimite Nobel caps (RWS) are just as hot as the Magnum caps and work well with most synthetic powders in a rifle.

 

[Elgatodeacero]

The CCI Magnum #11 caps are designed for single shot percussion arms.

When used in cap and ball revolvers they will split and fragment causing malfunctions.