I got an answer for my question regarding number and size of shot contained in a 10 pdr Parrott (2.9") canister round. It's not a short answer but the detail makes for an interesting lesson in geometry, ordnance and the Civil-War-era military-industrial complex. I quote the entire answer from David Gotter, to whom I was refered by Jack Melton of CivilWarArtillery.com:
"Jack Melton forwarded your message on to me regarding canister shot for 3" Parrot rifle. First question, shot count .. they were arranged in a 7 layer stack, 6 around 1 in the center, 7 per layer which should yield 49 ( 7x7 ) but there was not room in the stack for the 7th center ball, as the shot in the outer layers sit in between the 'shoulders' of the shots below, the shot in the middle sit on top of each other, so the center stack rises faster than the sides ... only 6 will fit in the center column ... so 48 pcs per round, pretty much across the board regardless of caliber. In smoothbore guns, the assembly was the same, only 4 layers instead of 7 yielding 27 shot per round. ( howitzers were different, 4 layers of 12, 9 around 3, 12per layer, 4 layers because they laid up evenly, for a total of 48 ) but there were exceptions in most canisters, and the Confederates would dump in just about anything that would fit in the can. Shot diameter was usually dictated by bore diameter. If everything was a tight fit, a 3" bore would use 1" shot, in the 6 around one configuration ( use a handful of pennies .. 7 will do ) if you lay them out properly, you will see that they line up 3 in a row, crisscross, so 3 shot side by side will equal 3", now you have to subtract for the thickness of the can, ( .005-.010" ) and allow for 'windage' ( loose fit ) for a muzzleloader, another .010" typically, so a 3" gun would use a shot 'set' of approximately 2.80" or shot diameters of .90/.95". It's not a perfect formula, but comes pretty close. I have a 3" canister in my collection that uses that shot size, but Hotchkiss manufactured canisters for 3" rifles that used 3/4" shot, ( about 75 pcs ) .90" shot, 48 pcs, and a can with 1.2" shot, 4 per layer with no center shots ( use quarters in a layout of 4 and you can see how they'd lay up zig-zag on each other, total 28 shot in that can .. I have one of each of the Hotchkiss canisters as well. Absterdam used the 'ugliest' canister I've met, it had a mix of .65 cal lead musket balls, .80" dia iron balls, steel 'cookies' punched out of 1/4" plate about 3/4" dia, and 'needle like' clippings about 2" long from the same 1/4" plate that were about 1/4" square at one end, and tapered down to a point on the opposite ... one of those needles scooting around inside you would ruin your day. The Absterdam canister I have is a 3" also. Dyer made canisters for 3" guns, long pattern and short, mostly short ones, and typically they used a 'loose pour' of .65 cal musket balls, but one pattern of Dyer used lead slugs very similar to 'Tootsie Roll' lead chunks. I have seen the lead 'slugs' in canisters and as shrapnel in case shot shells. Does this suitably muddy the water, or help you with your question? A 'safe' answer to your question would be 48 pcs of .90" iron shot. All canister shots were packed in fine grain sawdust, to keep the shot from wiggling around in the can, and possibly chafing thru the sides of the can ( that's the basic assumption amongst collectors ... all the 'experts' died about 100 years ago. ) If I can help you more, please let me know. Regards, David Gotter"
Hope you enjoyed Mr. Gotter's reply as much as I did.
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