The cannon we used to shoot was made from a section of a rifled 75 mm cannon barrel, AIR. The owner created measured and pre-made charges of black by cutting a piece of cardboard to bore size, placing the powder charge in the center of it, and gluing a round piece of tissue paper to the cardboard (enclosing the powder).In use we would carefully ram the charge down bore against the breech with the power charge facing the breech plug, then take a little steel prick and push it down through the touch hole, penetrating the tissue. Then a length of cannon fuse would be carefully inserted down the touch hole into the punctured tissue paper and into the charge.
The projectiles would be patched with a snug fitting cloth patch. I've seen oranges cut pine tree limbs off that were half the diameter of the orange. Funny story about the owner: He took a slice off the cannon barrel about 3/8" thick to use as a ring gauge for sizing the projectiles. He was standing in the fruit section of a local supermarket in front of the bin of loose oranges, trying them for size with his ring gauge. He'd test several, find them either too large or too small in diameter, and replace them into the bin. Every so often he'd find one exactly the right size and put it into his shopping cart. He noticed a woman watching him. When their eyes met she said to him "Yer awful particular about yer oranges, ain'tcha? He just nodded and went on about his sizing making a great show of it.
He would bring the cannon out at the SC State Muzzleloading Championships that were hosted by our home club, mostly for the enjoyment of the kids, and I would help him load a fire it. They absolutely loved it. He downsized some loads to the point that we could load one with an orange, tilt the barrel way up, and the kids would stand downrange and catch the orange with their hands, kinda like a "blooper". The owner was a very close friend of mine and a Marine aviator. He flew F4-U Corsairs in WWII and Korea. Absolutely the most interesting man I have ever been close friends with.
