ORIGINAL: yeoman
Even a duplexed load will fail if subjected to conditons of barrel condensation and humidity.
Cayugad - but will it fail as quickly? Igather from previous discussions that Pyrodex attracts water more readily than BP, so it would stand to reason that BP at the fire source would increase the liklihood of dischard, no?
Maybe it is just where I live, but no matter what kind of powder I use, if I store them in an out building over night ... I run a real good risk of the rifle will not fire or might misfire.
If you have a lot of moisture in your area, I would suggest shoot the rifle off at the end of the day, or pull the charge if possible.. Then clean the rifle and start fresh the next day.
While that is a lot of work, the chance of missing a big shot because I was not willing to put in some effort cleaning a rifle just does not seem like a good trade off. Others will leave the rifle for weeks. I seldom let them sit over night.