The following video is one of those high speed videos we showed on the thread called Cancer Shoot or something like that. What we didn't show before, was the artillery piece which shot the 120 ball canister load of .75 cal. balls and what happened to the canister container. The actual opening of the container happens so quickly when it reaches the muzzle, that the volumes of flame and then smoke cover the disintegration process completely. You have to remember that in muzzle loading artillery the blow-by gasses are voluminous because of windage. These gasses precede the projectile and mask the changes that are occurring to it while it is within approx. 10 feet of the muzzle.
Tracy and Mike
The footage here is shot at 1,200 frames per second. At least two pieces of the canister container are following the shot cloud pretty close to the center of it. One is the 4" dia. 3/4" thick baltic birch disk at the container's bottom. The other one or two pieces are what's left of the aluminum container cylinder or top. You can see two balls that lag behind the main cloud also. Click on the image to play the clip.

Here is evidence that blow-by gasses and smoke mask the muzzle of Black Powder Artillery. Even with high speed photoraphy, in this case at 1,200 F.P.S., you simply cannot see what's going on closer than 10 to 15 feet of the muzzle. Click on image to play clip.

Pieces of the aluminum container with lead ball impressions formed at the moment of firing. The malleable-iron solid shot form the background in this photo.

A picture of the 4" bore, one-half scale, U.S. 1797 siege mortar which was used to fire the canister charge.
