Artillery Shell legal limit.

[displayfireworks1]

Just for something fun to do and at the same time learn something. In this video you will see the contents of a 1.4 artillery shell being weighed. I did not weight the lift charge on this shell. The question is what is the legal limit for the contents of a 1.4 artillery shell in United States? Is that number separate from the lift charge? Please include a link to back up your answer if you can.


http://www.youtube.com/watch?v=b1Dq9QwGpsQ

[pyro92]

From what I hear and read the legal limit for a 1.4 reloadable shell is 60 grams, including the lift charge. I know I've found sources to back this up but I'd have to find them again.

[pyro92]

I am interested to know if this applies to cakes as well. I know the max size of a consumer shell is 1.75", but a cake can have a shell(insert?) of up to 3" or something close to that. I'm guessing that the answer is no because that would lead to an obvious OL, unless its only an 8 shot cake.

[displayfireworks1]

I did not weigh the lift charge on this shell. I will wait and see what kind of answers we get on this one. I have a feeling the requirement will be the combined weight of the lift and the contents.
Of course as users of fireworks, we really do not need to know all this. We kind of just go by what it looks and sounds like.

[californiapyro]

It is indeed 60 grams

http://www.fireworksland.com/html/statelaws.html

I have heard but cannot verify that 20 grams of this is reserved for lift. I believe this is why we are seeing more and more "mine to break" shells, since 20 grams is obviously way too much lift for a 2 inch shell. this may also be why shells like the famed excalibur contain heavy clay plugs, so that a monstrous THUMP occurs when the shell leaves the tube :)

[Palermitano2]

I say 60 grams total with lift charge hit the link and scroll down to table 13.

http://www.nfpa.org/assets/files/pdf/research/pyrotechnicsliteraturereview.pdf

[jknepp1954]

60 gr w/lift charge. 10 gr is the lift charge limit, not 20 gr as Cali pyro says. So that reserves 50 gr for the stars etc...

[Pyro Nation]

That is interesting to know... I have wondered how the 2 - 3 in shells in the Tubes for 1.4 would be then...

[Palermitano2]

That is interesting to know... I have wondered how the 2 - 3 in shells in the Tubes for 1.4 would be then...

Its still 60 grams as you can see when they break they get smaller and smaller not to many multiple break shells on the consumer market.

[californiapyro]

hmm... lifting a 3 inch shell with 10 grams, that would be interesting to know how they do it. i need to get me some of that lift! haha

[Palermitano2]

from what I understand and correct me if I am wrong but it doesnt take that much lift charge to get shells in the air. The traped gases are what shoot it upward.

[PyroJoeNEPA]

hmm... lifting a 3 inch shell with 10 grams, that would be interesting to know how they do it. i need to get me some of that lift! haha

The lift charge is usually 10% of the weight of the shell. A typical 3" shell is around 70 to 90 grams, so 7 to 9 grams is more than sufficient.

[PyroJoeNEPA]

In the name of science I dissected a 1.75" ball shell [didn't have any canisters left!!!] I used a Sky Tiger which is a very solid well made shell. The overall weight of the shell [casing, fuse, etc] was 63 grams. The lift charge was 6 grams, the stars & burst charge [surprised me that is was BP on rice hulls in such a small shell] was 29 grams and the empty casing & lift cup was 28 grams.

[PyroJoeNEPA]

Exactly correct! Just like a bullet in a gun barrel. That is why a shell in a slightly larger mortar doesn't get the altitude a snug fitting shell does.

[indianahx]

Exactly correct! Just like a bullet in a gun barrel. That is why a shell in a slightly larger mortar doesn't get the altitude a snug fitting shell does.

Also why you get more "thump" out of a canister....more of the area filled with "shell"

[californiapyro]

hmm interesting, i thought the standard weight of a 3" was between 120-150. but i guess having a tight shell makes up for it

[Dart]

Does anyone know what the purpose of the clay is...?

[Pyro Nation]

from my understanding the clay bottoms are like plugs in a HDPE mortar tube for reloadable shells

[Palermitano2]

from my understanding the clay bottoms are like plugs in a HDPE mortar tube for reloadable shells

I agree i think its easier and cheeper to use clay then to use wood.

[Dart]

I'm refering to the clay in the shell itself. 1.3" cannister shells just have paper/cardboard top+bottom but for some reason 1.4 has clay as part of its construction.