I bought several cans of FF black powder a few years ago and have about half a can left. I also have about 50 primer caps left from the same purchase. I have a buck tag for the muzzleloader season and am considering buying a new can of powder and new caps.
Am I increasing the risk of misfires by using this old powder and the old caps? What is the shelf life for powder and caps?
Powder and primers have been stored appropriately so they are dry. I have just never had "leftovers" before, always shoot enough to use it all up in a year. But this year I got too busy to get out much and use up all my powder and primers. Hate to spend money to buy new stuff if what I have will work but also hate to have a nice buck step out and have a misfire, which could happen anyway, but don't want to increase the chances.
My first year hunting I was using powder that my dad had left over from the last time he hunted, 4 years before and he had it for a year or two before he stopped hunting. My first deer didn't ever know the powder was 4 times older than he was. My dad still has primer caps from when he found a buy on get one sale on them about 12 years ago that he's still using up, no missfires yet. Just keep everything high and dry and it'll be fine to use.
As noted, if stored appropriately - cool and dry - the shelf life of both is decades. I am using primers now that were bought in 1989; they all work.
But....I had left a tin of musket caps in an ammo box with some moisture inside. Almost all of them were duds a couple of weeks later.
REAL black powder has no shelf life if stored well. Substitutes like pyro and trip 7 im convinced loose effectiveness if several years old.
I had a opened can of pyro that sat in the airtight tub with several cans of opened Goex FFFG for two years. Pyro had a noticeable decrease in effectiveness and reliability. And subs dont work well to begin with for traditional guys. I ended up using the pyro for "fun" stuff other than shooting...
I can't remember which company it is --- Dupont maybe. Anyway, in their headquarters they have a couple pounds of blackpowder stored in water. Yup, they have a few pounds in a huge glass jar with about ten inches of water over it. Blackpowder is wet and put in big cakes. It is then dried, crushed and sieved for grade. If it gets wet dry it and shoot it.
I have about a thousand caps left from a large purchase in 1982 and they work just fine.
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