black powder cartridge cannisters for cannon

i'm not a black powder shooter. but i thought that someone on this section might know the answer to this. starting around 1810 u.s. ships started encasing the powder for their ships inside sheet lead containers. this kept the powder from getting damp or wet. it was loaded into the cannons this way. after firing, how was the remains of the cannister removed from the bore? it was not consumed by firing. i did a lot of research on this, and, can find nothing as to removal of the sheet lead after firing. maybe the answer is simple, thats why there was no reference to my question. on another note; during my search i discovered that lewis and clark had the powder sealed in sheet lead containers to keep it dry and did not keep it all in the same place.

Muzzleloading cannon are "wormed" using a spiral jag device which removes the residual lead foil, then sponged to kill any latent embers before being reloaded. The powder bag is then pierced through the vent before inserting a friction primer which is activated by pulling the Cotter pin of the primer with a lanyard. From Gilhams Manual for Volunteers and Militia, Instruction for Field Artillery, 1863.

Lewis and Clark cached their lead barrels of B/P for two reasons the lead barrels were cast into balls and gave them a near infinite supply of balls and powder for their return. They had state of the art Springfield rifles from Harpers Ferry armory. They were as near perfect outfitted for their task at hand as possible, lost one man due to appendicitis in two years. Pretty fantastic journey when all said and done.

Not only that, Randy. The lead in the casks was exactly the amount needed to cast the balls for that amount of powder. Lot of sophisticated thinking going on then.

guns were wormed after each shot even after they started using cloth powder bags.

I think the lead containers were bulk storage and not what was loaded into the gun.

What R-71 said.

"""""""No canisters from the expedition are known to survive, although at least one may still lie buried on the trail. What more can we infer from the records of the expedition about Lewis's lead powder canisters? Lewis's journal entry of February 1, 1806 relates that the canisters were made with eight pounds of lead. This matches records of supplies obtained in Philadelphia in May of 1803. The “Invoice of Articles received from the Arsenal for the use of Capt. Lewis,” dated May 18th 1803, includes “420 lbs Sheet lead.”3 Note that the invoice specifies sheet lead, not lead pipe, and not lead ingots for castings. On May 25, 1803, Israel Whelan, the purveyor of public supplies, paid George Ludlum, a plumber at 96 South Second Street, $26.00 for “Making 52 lead Cannisters for Powder.” Using the 420 pounds of sheet lead, that amounts to a trifle more than eight pounds of lead per canister, confirming Lewis's description. As a practical matter there is no excess lead for waste in assembly, so perhaps the finished canisters used slightly less than 8 pounds of lead apiece.""""""""

As the above paragraph states Capt. Lewis purchased 420 lbs of sheet lead and had 52 canisters made George Ludlum. No other lead is listed in their supply list. Lead for casting balls would have been purchased in ingots, not sheets. There is no other mention of lead being purchased for the expedition. There were 15 ball molds purchased for the Harpers Ferry rifles.,,,Ed

Here is the complete article
http://www.westernexplorers.us/Powde..._and_Clark.pdf

I would think the lead canisters were melted to make projectiles balls or bullets.
I doubt 8# of lead got tossed to the side of the trail when ever a powder canister was empty.