Len,

This is GREAT info. I'm envious of you and your toys!

I suspect that what you are seeing with the rifle would have prompted the switch back to lead musket balls and a much higher shot count. If the gun tends to string them out, then having them deform and spread as a result would be good, plus the greater count will provide more opportunities for any outliers to hit.

I'm curious about any optimization/comparison you've done for shell vs. case too. Like what is the optimum burst distance for normal low trajectory fire? (50-75 yards sounds about right, maybe more to make sure the burst is before the target.) Do any fragments fall between the burst point and the gun? (Rough inspection of the projectile's velocity vs. the small burst charge suggests that they could not.) How many more fragments are falling on a wide target-set with case vs. shell?

Does anyone fire polyhedral cavity shell? I've wondered if it would perform noticeably better than round cavities because of its uniform fragmentation pattern.