Frederick,
Thanks for the reply. I presume "rifle ball" infers an elongated/conical shaped projectile. I didn't realize that buckshot could be used by itself rather than with a ball, but was that a common practice? I understood that even with "buck and ball" that the ball and buckshot would travel separate trajectories. If so, it would seem to be advantageous at short ranges due to the increased odds of one of the components making contact.
It is interesting to conjecture which regiment fired the buckshot or round ball that struck specific Federal soldiers at Gettysburg. A soldier of the 134th NY was struck by three buckshot - his regiment fought directly opposite the 6th NC. A soldier of the 157th NY was hit by a round ball, which suggests it came from one of BGen Doles' Georgia units. BGen Paul was blinded by buckshot while facing Rodes' division.
Your point about such records being mainly limited to surgeon observations is well taken, but can't this sampling method be generally extrapolated to the overall casualty population without skewing the results too much? If not, what other factors need to be considered? I realize buckshot would be less likely to cause a fatal wound, but some soldiers who were superficially wounded in this manner might not even report it to the surgeon. Artillery wounds are a different matter. Solid shot was always nearly fatal but then again was often reported by other observers when it did occur. Tom