.705 caliber....my, My, MY!
That’ll leave a mark.....
The American rifled Musket, used in the war between the states, was .68 or .69 caliber.
Some rifles were small caliber, say, .45. Now that is considered “large caliber”!
Basically 12 gauge(a little less) or more correctly 12 bore. It was the size of the smooth bore muskets of the day. Using a round ball that size is not as impressive as it sounds. But It it still is quite impressive.
With the same bore smooth bore you like the Brown Bess one could launch 4 rounds per minute. The Baker? 2 rounds per minute. It is a specialty weapon used for sniping. We did the same thing with the Kentucky (or more correctly Pennsylvania ) Rifles.
A better British rifle of the era was the Ferguson breech loaded rifle.
The British Brown Bess, a generic term, was .69 caliber at the time, whereas the colonialists typically used a .63 caliber.
Ergo, the analysis of the battlefield remains turned up piles of shot from rotted bags left by fallen, and weighing the rounds gave a pretty good picture of the layout of the sides.