Burning embers?

[channel12]

I often see references to the dangers from burning/smouldering embers when pouring powder down the barrel of your muzzle loading long gun. The question is, what is smouldering down there? I can't imagine it's the black powder and I would think the patch when using patched ball isn't staying in the breech to smoulder.

I am wondering if this idea is from the use of bagged charges in cannons where there was a high probability of fragments of the bag still smouldering in the breech ? The practice then was the gunner placed his thumb, protected by a leather thumb stall, over the touch hole when the cannon was being swabbed out and reloaded.

I currently load my ML rifle only with powder and a naked REAL bullet sans lube so I would be surprise if there were any burning embers in the barrel after I fired

[ovenpaa]

I use toilet paper for wadding with and suspect that is what is the cause for me when shooting a .700 cannon. Certainly I always patch the barrel out after every shot.