For 20 years I told visitors at Stones River that grape shot was for large caliber cannon, principally at sea. The individual balls in a “stand of grape” were, in some instances, the same diameter as the bore of our 1841 six ponders. Grape was intended to destroy the top hamper of a sailing ship & secondarily as an antipersonnel weapon. In effect, it turned a 36 pnd gun into a giant shotgun. The stand of grape for the 11” guns that the Neosho fired during Thomas’ attack at Nashville in Dec 1864 weighed 128 pounds, if memory serves.
Despite the “… grape & canister…” referred to in thousands of soldier letters, grape was not issued to field guns. You can imagine my astonishment when, at the visitor center museum at FT Defiance in Clarksville TN, I saw a stand of grape for a six pnd cannon! Never say never where the ACW is concerned. It had to be some kind of naval/ gunboat thing.
Canister consisted of 28 iron balls that were of a diameter appropriate for the bore. It is, once again, a giant shotgun round. There was no bursting charge. The thin metal can that housed the canister balls would come apart as the round left the muzzle. At 300 yards max effective range, the balls were in a spread about 90’ wide.
It is generally believed that the small number ( 5 +/-) of canister packed in the ammunition chests were only used as a last ditch defense. While that is true, canister was also used in aggressive ways, as well.
To fire on a battery or cavalry, a solid shot or bolt was loaded & two cans of canister balls were rammed home on top. Wilder & Eli Lilly, whose battery was assigned to the Lightening Brigade, reconfigured the ammunition chests to contain more canister rounds. At Hoover’s Gap, June 1863, Lilly’s 3” rifles fired “long range canister” at Bate’s attacking infantry. The solid bolt & three canister wrought havoc.
Another antipersonnel round that is not generally known outside the Redleg community. Dummies consisted of bags or socks loosely filled with pieces of scrap metal or lead balls. During the Atlanta Campaign & at Franklin Union 3” rifles were loaded with a powder charge, solid bolt, canister & then crammed to the muzzle with dummies filled with Minnie balls. The commander of a battery that engage closely packed CSA attackers with dummies stated that “… I heard the report of the gun followed by the sound of the bones…”
Spherical case was the invention of Sir Henry Shrapnel, it consisted of a thin walled sphere for smoothbore or bolt for rifles filled with pistol balls & sulpher. A timed fuse & small bursting charge caused the case to break open scattering a shower of fragments & balls to impact personnel with great effect. Ideally, the Shrapnel round detonated 10 meters above & in front of the target.
The momentum alone caused the fragments & balls to impact the target at a speed approaching the speed of sound. The air bursts of spherical case/Shrapnel would have made the air above the target look something like Berlin in 1945. General Hanson of the Orphan Brigade was mortally wounded by the fuse of a CSA shot.
Shell was exactly what it sounded like. It was a thick walled sphere or bolt filled with powder. A timed fuse caused the shell to explode above a personal/mounted target after 2 seconds of flight/about 800 yards, for example. The jagged chunks of the case impacting flesh at near the speed of sound was devastating. The bore of 6 pnd 1841 model cannon was too small for shell.
Mortars, Howitzers & Napoleons fired shell in high arching trajectory with fused cut for air bursts or after impacting structures. At night, the trail of sparks from the timed fuses acted like tracers across the sky.
Rifle bolt shells could have impact fuses. For obvious reasons, smoothbore balls did not have impact fuses.
To batter in a door, gate or wall, a blank charge was used. The cannon was pushed up against the surface & the muzzle blast would create a breach for infantry to jump through. At point blank range, a solid ball could bounce back & kill the canon crew.
Hope this removes any confusion about artillery rounds. Feel free to seek clarification or ask related questions. I am National Park black powder cannon gunner who has been answering visitor questions for over two decades. The only dumb question is the one you did not ask.