Not realistic, but keeps it from being real
After the battle of Gettysburg, guns collected off the battlefield were found to contain more than one “load” as well as the ramrod. Quite a few rifles were found to be loaded with up to 5 bullets. In the excitement of battle, many soldiers forgot to aim and pull the trigger but just kept on loading.
Since the percussion caps occasionally do NOT set off the powder in the chamber, especially when the air is damp, then I can certainly see why real infantrymen during the CW may have kept on loading even though they weren't firing. They did not know that they were not firing.
After the battle of Gettysburg, guns collected off the battlefield were found to contain more than one load as well as the ramrod. Quite a few rifles were found to be loaded with up to 5 bullets. In the excitement of battle, many soldiers forgot to aim and pull the trigger but just kept on loading.
But you see, all it takes is one misfire for that to happen. If you don't load properly the first time, and if in the excitement of all the cacaphony and danger of battle you don't realize that the weapon didn't discharge, you would load in another round on top of the defective initial load. Then if the initial defective load still doesn't fire, the fact that there is another load in the barrel on top of it isn't going to make any difference.Rinse.
Repeat.I would think that there must have been cases when the initial load finally did fire after misfiring once or twice - and, if so, it seems likely that the musket would have "blown up real good."