Hollow based minie balls were used well after the civil war for hunting and are found all over the country. The government sold off all it's muzzle loading firearms as surplus after the war and the adoption of breech loading weapons, and these muzzle loaders were used by civilians for many years after the war for hunting. Also remember that the confederates were allowed to keep their weapons for hunting purposes and these muzzle loaders and minie and round balls were used to hunt right up to the late 1800s. A found minie, unless found on a battlefield is not necessarily a CW era bullet. There are also modern molds for hollow base minies, I have and use one myself and you will find a lot of them in the woods behind my house as I have target shot them there for over forty years. Cool finds, but hard to really date the bullet.
I will concede the point that bullets are difficult to date.
However, I will point out that
military use of muzzle loaded, hollow-base Minie' balls lasted barely more than a decade in the US as the "modern" armies of the world quickly moved breech loading rifles after the Austro-Prussian War of 1866.
To my knowledge, Confederates who surrendered were not allowed to keep muskets. At Appomattox, Confederate officers were allowed to keep sidearms, but rifles, carbines, and artillery pieces were surrendered and largely destroyed. Much of the surplus of Federal weapons was sold to European governments.
Some surplus muskets found new civilian life as shotguns. I own a British made P1842 that was stripped down and sold in the 1880's as a cheap shotgun. I have also seen a "Richmond Rifle" at the NRA museum stripped into a shotgun.
I couldn't find any reliable numbers but estimates I saw put the number of rounds purchased by the Federals at @ 470,000,000. Estimates I saw for the Richmond arsenal say @ 70,000,000 were produced there during the war. The Atlanta arsenal made another 9,000,000.
I won't belabor my point but, for my money, bullets made/used during the American Civil War era constitue an overwhelming percentage bullets found by relic hunters.
In closing, I will say a buddy of mine found a reproduction Minie' in the woods near Bristow, VA. We knew it was a repro because it did not have the lovely gray-white patina of balls that have been in the ground for 150+ years.
