Richard's spot-on about the Minnie tumbling. They did that inside bodies of men - "the accursed Minnie, coursing through the soft parts of the body, shirking the bones and traveling around them, unlike the round ball which smashed the bones asunder creating most grievous wounds". - or words to that effect by the Surgeon General, Crimean War.
Note perhaps of interest, from the Firearms of the American West, notation about the shooting properties of the Minnie in it's various form and diameter. The "Jaugers", which (some) many called the issue .58 Minnie rifles, were less accurate than the .69 Minnies which were used in the rifled muskets, ie: the model 1842 musket and the previous, musket 1822?, which were rifled to shoot the 730gr. Minnie bullets.
Should just about be able to measure the one side of the mould, from those balls, right beside the mould's dividing line. By 1820something, the round balls for the muskets had been increased in size by 10 thou, to .650" while the power charge in the paper ctgs. had been reduced to 135gr., which included the prime. The 1842 Musket was the first cap lock US musket.