> A standard civil war battery reuired about 75 yards in width.
> This implies two batteries in 150 yards but hub-to-hub

Oh! That's actually the exact number I was wondering about. The batteries in question would have been the 11th Ohio (6 pieces) and the 3rd Ohio (6 pieces) at the Battle of Raymond.

I thought a 6 piece battery generally consumed about 90 yards of space.