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View Full Version : Sabots on artillery shells



Jordan0885
07-19-2020, 04:47 PM
Now I'm no professional, and I've never made any fireworks other than ill advised things when I was younger, but I like to read and watch videos about all sorts of things just to have a better understanding of how things work and the idea popped into my head about artillery shells while watching videos of people making them. If you put a sabot on them, say some kind of foam that's already split in half, you would gain height from the normal lift charge, or be able to use less lift to achieve the same height. Just wondering what some real builders think about it. I know it's probably not feasible as the cost of less lift probably wouldn't make up for the cost in time/money to make them, and it'd probably make a helluva mess. Just want to hear you all's thoughts.

PyroJoeNEPA
07-19-2020, 05:56 PM
I don't see where anything would be gained. Shells tumble when shot out of a tube---a good example is to watch some of the you tube videos of the large "salami's" shot in Italy and Malta. You can see them tumble when they get in the air. Also, a ball shell spins---this can be seen if you look at the tail when they are fired.
Typical 1.4g canisters do not have "rising tails" on them, but I have glued some on to see what they do----they spin!
Rockets, on the other hand have a nose cone [1.4g stuff] to aid in keeping them straight. Doesn't do anything for trajectory, but does help with aerodynamics.
Interesting question you brought up.

Rosko2
07-20-2020, 10:44 AM
I see the problem would be how a sabot works. On a bullet, it's made to trap gasses that would pass around the bullet and engage the rifling in the barrel when it's fired causing the bullet to spin which aids in down range aerodynamics. With a shell, you'd have to load it like a muzzleloader with a ram rod if the sabot was going to be effective. Now you have a loaded shell that when goes off, the sabot is supposed to expand slightly making that seal. I don't see this happening with a consumer shell in a cardboard tube, let alone the safety aspects of having to load the shell correctly with the ramrod. It would definitely work though if you have a strong tube and seated the shell properly. I've theoretically accomplished the same thing by wrapping shells with masking tape at it's widest point. The tape takes up the extra space around the shell when put in the tube and allows the shell to travel higher due to more pressure behind the shell when it goes off.

Jordan0885
07-20-2020, 03:42 PM
I wouldn't want to see it on consumer stuff. After watching a ton of videos on YT of fireworks demos this year then reading through comments I don't have much faith in the average user of fireworks. I may have to make something up and try to measure the difference between the two. Probably won't ever get around to it, though. You have any idea about how much more height you got with the shell with tape on it?

RalphieJ
07-30-2020, 11:30 PM
Isn't anyone concerned that the higher pressures will cause the shell to flowerpot? Since all of the 1.4 shells are bottom fused, I would be fearful of this happening.

displayfireworks1
07-31-2020, 08:00 PM
I didn't know what a sabot was. Sounded like a Jewish holiday beginning at sunset on Friday. LOL . To see how these artillery shells, canister artillery shells and even display shells behave once they leave the mortar, shoot some of them during the daytime. This is always a problem for pattern shells like smiling faces, hearts etc. You can never depend on them breaking in the correct orientation. This is why its best to shoot them in flights of multiples in hopes that at least some of them break correctly. All these shells sometimes spin around all over the place and still other times they do not spin at all. A sabot may be beneficial on a rocket and some do have them.

PyroKing31
08-01-2020, 10:06 AM
I didn't know what a sabot was. Sounded like a Jewish holiday beginning at sunset on Friday. LOL . To see how these artillery shells, canister artillery shells and even display shells behave once they leave the mortar, shoot some of them during the daytime. This is always a problem for pattern shells like smiling faces, hearts etc. You can never depend on them breaking in the correct orientation. This is why its best to shoot them in flights of multiples in hopes that at least some of them break correctly. All these shells sometimes spin around all over the place and still other times they do not spin at all. A sabot may be beneficial on a rocket and some do have them.

A Sabot on a rocket wouldnt really make sense. It is a shroud around a projectile being fired out of a tube, usually the barrel of a rifle or artillery. Abrams Tanks use them for their Depleted Uranium penetrator rounds. Its an ablative spacer that ejects once the projectile leaves its barrel. allowing the smaller projectile to keep going. They usually have an inverted cone shape on the front that allow it to blow away more quickly.

I could see this being used on 1.5 festival balls into a 1.91 tube or something along those lines.

Current 1.75 ball shells and canister shells are close enough in diameter that a sabot would be excessive in material cost and labor, so as what Rosko2 Said a few layers of Magic tape to close the "gap" would be best, but I'm not sure how much of a gain you would get in consumer given the irregularity of lift charges and time-fuse, best would be to take a sample size of say 12. Take all of the lifts out and make sure they are even. "sabot" six of them and fire them in a chain with the other 6 and see what happens.