Leaving the powder in a Blackpowder gun
 

OK now the guy made his last hunt and he had the gun loaded for 3 days and no rain. He takes primer out before leaving the blind and installs a primer on the next trip to blind. He came home from Toledo and went to shoot the loaded gun and just the primer went off. He says I have been carrying a dud rifle for a few days? He puts 2 new white hots in and boom. Do you leave your BP gun loaded or shoot it after everyday? Or just dump the powder and knock the bullet out the back end. Some say put tape over barrel. Moisture must be quick to kill the black powder. What are ya'lls thoughts on this?

With Triple Seven powder, I often left the powder in until I happened to fire it next. It always worked when ignited with a 209 shotshell primer.

Black powder and Pyrodex are much more iffy, and much more corrosive also.

I just remove the breech plug and push the bullet through.

What was he using for primers....When I was useing #11 caps I always shot a few caps before I went in woods. This was after I shot at a doe and the cap didn't really go off because of moisture on the nipple. 2 caps after didn't ignite the powder because the first one clogged the nipple. #209 shotgun primers shouldn't fail. Use pellets and it should still shoot the following year. I never had them fail with the 209 primers.

leaving the powder in a black powder gun
 

He was using the Remington 209 for made black powder. I told him after every shot to check the breach plug hole. I have read that guys up north use them for 3 weeks and said to store gun in camp muzzle down.

If black horn 209 powder ur good to leave loaded as long as u want. Anything else is suspect after a few days

I have left mine loaded for a couple of seasons and it still fired just fine. I use #11 caps and pellets. The pellets should not hurt your barrel if left loaded. I don't think you can say the same for loose powder. If weather conditions are damp I would definitely not keep it loaded. Then you are asking for a miss fire.