Speedenforcer, you're welcome.
Pipedreamer, when giving a program/talk to a relic club or school class, I almost always mention Hollywood's incorrectness in showing cannonballs exploding when they hit the ground. I do explain that Hollywood does it because it's safer and simpler than trying to simulate a cannonball airburst among the actors. But still, a part of me groans every time I see groundbursting cannonballs (meaning, detonation upon impact with the ground or other solid object).
Jonpatterson, the secondary purpose of the sabot-&-straps is to provide a simple way of firmly attaching a propellant-powder bag, thereby producing "Fixed" ammunition (projectile and powderbag connected as a single unit), which significantly speeded up the cannon loading process.
In actuality, of course, the only two civil war fuzes capable of producing a cannonball groundburst, the (US) Tice Concussion and (CS) Broun Concussion, were ALMOST NEVER used in cannonballs. Due to reliability and safety concerns, the US and CS (respectively) Ordnance Departments declined to produce them beyond a small number for experimentation/testing. So the fact that they did exist is not a viable excuse for Hollywood's incorrect portrayal of cannonball explosions.
Note: The paragraphs above were modified after posting, for the purpose of clarification.
Regards to all,
Pete