over night is pure exaggeration. I shoot a ton of pyrodex every year, hunt with it at times, 9 days straight and have not had anything turn into a crap bucket over night.
Not over exaggeration whatsoever. I had it happen to me, though nothing exterior. It rusted my barrel horribly and took countless hours to fix.
This is from a test run on steel plates after 4 days in the garage in Missouri during a summer:
As you can very well see Pyrodex ate the metal far worse than BP. His complete testing and findings are available on another forum. This was after he finally cleaned them up, and with T7 he didn’t go quite as far as it wasn’t needed.
As to not being able to clean your rifle. Use an oil such as Ballistol. The fouling will soak up the oil and keep moisture off of it. I tested this myself with 2 revolvers down in Texas where the humidity is quite high, and this was done during the summer and in my garage.
As to my rifle shot with loose Pyrodex, I trusted what a few CASS shooters said, that they had left their guns for quite some time with no issues. I shot my 2 revolvers and rifle and didn’t come home until after dinner and only cleaned the revolvers trusting that my rifle would be fine the next day. Not true whatsoever. It was a mess! And the above picture shows how much worse Pyrodex can be. But that’s not why I hate it. It’s the quality of the fouling I don’t like at all, which may not amount to much in a rifle, but on my revolvers it has a sticky quality to it that’s everywhere. And that it’s energetic properties don’t stack up in handguns for hunters.
A BP gun should be cleaned after shooting so how corrosive it is should be a moot point. And if time is against you oil is your friend.
*EDIT*
It took a few years to not get an orange patch back when I checked after several months of sitting from that rifle barrel. Sitting I used Ballistol, and knowing people said it’s not a good long term storage oil I’d check it a few times each year. It’s finally been coming back clean.
Regardless there’s no more Pyrodex for me. And I still have a small amount of P and RS sitting there.