How long do black powder and caps last?

[Rigmarol]

How long does Black Powder and caps last?

Around my house about 6 months.

How long does substitutes last?

Around my house a bout 2 months longer than real Black powder or until I can order more...

Seriously, if stored properly it's good for many years.

I had a jug of Pyrodex R for about 12 years then used it up recently and had no issues. Stored in a cool dry place the whole time.

Real BP doesn't stay around long enough for me to speak from personal experience on that point.

 

[indy1919]

Went to an Auction, and in the Garage was a simple Cardboard shoe box that had some Black Powder odds and ends, It had half a Tin of Musket Caps, and 4 tins of No 10 caps..

There was a receipt in the box dating back to 1965. (not for the caps)

The Garage was a cement floored unattached building with no heat or cooling.

All of the Tins showed surface rusting where the paint covering had been rubbed away. 2 of the tins had rusted shut so badly that to open them I was forced to open the tins with a screwdriver by bending the lid open.

Every darn cap fired. I did not toss any caps before hand,

No rust was inside the containers

 

[mec]

[I"]my cap & baller was a half-empty can of Pyrodex P that my uncle had for at least 30 years. Shot as good as the next [/I]"

A friend bought a can when it first reached this area (which would have made it about two years after introduction.) He didn't like it and left it in his garage until a few years ago. This involved temperaturers rangiing from +5f to +110F. Shooting it in revolvers, we found it a few feet per second slower on average than a new can and every bit as consistent as to extreme velocity spread. Would think that the different velocities might be a factor of lot variation as early gunwriter data tended to show p/dex slower than current results.

Have also shot black powder ranging from 50-100 years old with performance much like current goex.