In my Civil War Projectiles II,book by McKee & Mason.On page 67 it talks about case shot & lead balls ranging in size from 1.30",1.13",1.115",1.00" and.855" all the way down to .285".Weight in grains from
3443,2160,2075,1497 and 932 all the way down to 34 grains.That are some of the sizes that have been
field recover.So their are a lot of different sizes used in different ways.Cannons,Rifles and pistols.
I know that I have found several case shot in the 1 inch dia.Hope this helps.Congrats on your find,I love finding and lead pieces.
fortbball9