You have to remember that there were over 400 different types of small arms ammo used during the CW and nose cast or side cast is not held to one side. I have dug 1000's of bullets and field casting was not that prevalent except for some pistol ammo.
There is nothing farther from the truth. Yes when the war started the South did not have many foundries but it didn't take long for them to gear up and the South had some very fine arsenal after the first 2 years of the war The Selma arsenal turned out some of the finest artillery pieces as well as ammo. The also made small arms ammo for use in all the captured yankee weapons. One of the biggest suppliers of weapons for the South was the north.
The Selma lube groove bullets was a prime example of small arms ammo.
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