Thinking about the loading procedure with an 1859 or 1863 Sharps with loose powder got me to thinking.
Is there any reason you couldn't do the same with a cartridge rifle? Particularly a black powder rifle, even using smokeless powder?
Take for instance my Swiss Vetterli. Let's say I drop a bullet into the breech and snug it up to the rifling with a dowel or something. Snug enough so I can hold the gun skyward without the bullet falling out. Then I take a primed case, cut short so as it doesn't scrape the bullet, charge it with, oh let's say 23 gr of 4198, and carefully insert it into the chamber, holding the muzzle up so it doesn't spill. Once chambered, lower the muzzle, and close the bolt.
So long as there isn't any secondary projectiles- such as wads or cards- I don't see that this would cause issue. Or?
I'm just thinking that for guns with really long throats, this might be just the treat.