I might have struck some gold. Ohio Joe in reply #14 talks about the practice of the military back in the day of the flintlocks. The more I thought about it, it seems likely that former military men would have carried into their lives, after the war, the gun handling practices taught them when in the service. A little more digging took me to Brig.-Gen. Silas Casey's 1863 Manual of Arms. Pages 9-13 describe and illustrate the Army way to load a percussion long arm using a paper cartridge. It begins with the hammer forward on a fired cap. Once the paper is torn the powder is poured down the barrel then the ball is started with sprue up. No mention is made of what to do with the paper! Finally the hammer is put on half-cock, the old cap is removed, it gets recapped and hammer goes to full-cock. It makes sense that this is how a large number of former soldiers and sailors would have continued to load their percussion arms in the days following their service. Extra points for the general, safety of to serviceman seems to have become taken into consideration, and thanks to all who have replied.
Dumping a charge and ramming a
patched ball down on the powder, will often cause a patched ball to raise off the powder due to trapped air (think hydraulic effect) when loading a percussion rifle with a spent cap on the nipple and the hammer down blocking the escape of trapped air.
Under those circumstances air can be trapped between the powder charge and the patched ball, which can result in a burst barrel upon discharging the gun.
In 1863, percussion small arms during the Civil War would have been loaded by grabbing a paper-wrapped "cartridge", tearing the bottom of the cartridge off with your teeth, dumping the charge down the bore, followed by the slightly undersized conical bullet (with paper still attached) was rammed down upon the charge.
The paper rammed down on top the conical prevented the undersized conical from slipping/moving forward (creating an air space between charge and bullet) until the gun was fired.
Upon the gun's discharge the hollow base of the conical expanded to engage the bore's riflings.
This procedure lends itself towards an easy, and quickly, loaded conical bullet that was pretty accurate for the times, and allowed any trapped air in the bore to safely escape past the undersized bullet, as it (with remaining paper) was rammed home.
Soldiers of the Civil War, often took their rifles (muskets) home when leaving the service,.... so they were probably still using home-made "cartridges" with undersized conicals during civilian use.
THERE IS NO WAY,... I'D EVER ADVISE ANYONE LOADING A PATCHED ROUND BALL IN A PERCUSSION MUZZLELOADER, TO DO IT WITH A SPENT CAP ON THE NIPPLE WITH THE HAMMER DOWN.