Aerial Shells

[murderskill]

I have a question. I have 3 1/2'' launch tubes and 9/16 shells. I was wondering if anyone used the method with 1/8 tsp of Bp for lift? If so what is the max height? I will be inserting a small amount of flash in them and will later try smoke comp.I will be using 70/30 kclo4/al. But with the flash if it will be sitting for a while in the sehll itself will I need to add cab-o-sil? I get tons for free from school. Does it get more dangerous while the flash sits in the tube and if so will the cab-o-sil help?

 

Thanks alot guys!

[al93535]

70/30 flash should store just fine for many years in a sealed tube. It will not get any more sensitive or dangerous. I don't see any reason to add cab o sil.

 

As far as the lift is concerened, I suggest you do a test or two first. What kind of BP are you using for lift? Is it homemade or commercial? It depends on the lift quality, the fit in the mortar and the size of the grains.

 

I would start with trying 1/12th of the weight of the shell for lift, and see where that gets the shell. Then adjust accordingly.

[ewest]

Yes, I've used the 9/16" inserts and I shoot them from a 3/4"ID mortar. For the lift charge I use Goex and I've tried their 2FG, 4FG, and Cannon lift. I've tried everything from 1/8 tsp to 1 TBS and the results vary slightly, but not much really. They basically go anywhere from 20-40 feet high but no higher than that, even with 1TBS of lift. Those 9/16" shells and just way too light to launch high, wind resistance just takes over after a certain point.

 

I finally settled on 1/4 tsp Goex 2FG for my lift, simply because I have more 2FG and 1/4 tsp gets it up about as high as I want. I can't see wasting a bunch more lift to gain an extra 10' because they're already down so low anyway.

[_Po_]

Just a side note on that, use a dummy shell for the tests unless you've got a good test area. Shells are great for starting fires, nice big spread of little burning pellets. Just fill a shell with kitty litter (and tissues if you need some space filled) to get the same average weight as your loaded shells. And again, I know it's common sense, but sometimes we miss the simple things, make sure you do it in an open area, haha, don't want it coming down on a car or anything...or yourself.

[murderskill]

Im thinking about trying FF I havent bought any BP yet because i wanted to see what u guys would say first. Im going to check out wal-mart in a couple days to see what kinds they have.

 

Thanks for the info guys

[ewest]

Walmart where I live (Texas) doesn't carry BP. I can buy Pyrodex which is a substitute BP from the sporting goods store and I have used 2F Pyrodex for lift powder before, it'll work for that. but don't confuse it with black powder.

[Karl]

I have used Pyrodex before but it A) Isn't as powerfull / Is twice as expensive!

[joker5]

that is pretty much all i use , and here it is cheaper than bp.

[joe609]

Do you guys not make your own Bp or is it easier to buy it where you are?

[artificier]

this is my firework of the day :

http://media.putfile.com/shell-burst

 

1 ½ " spherical shell with chlorate stars and coarse BP and a little amount of flash powder 70/30

[PyroJoe]

It's easier to buy BP of course, but much cheaper to make! (if you have access to the materials) I figured I can make a pound of lift for about $2.50 since I cook my own charcoal. It could be even cheaper, since it is possible to get kno3 cheaper than I do. It is just as fast or faster than commercial powder as well.

 

BTW Artificier that video is 2 seconds of nothing.

[artificier]

yes its very short

 

its a little difficult to get material.I make my own charcoal but KNO³ cost 3.00 $ to 6.00 $ for 100g

[murderskill]

I dont have a ball mill..nor money for the chems right now..so commercial BP will have to do for now.

[ravaz]

Here's a quick video of an 8" Red to Blue chrysanthemum with white flitter pistil we were testing on Sunday night. Actually, it wasn't really a test, we were just bored and haven't lit anything in about 2 months.

 

The blue doesn't get picked up by the camcorder (comes up red), and I went cheap on the flitter stars because they were 9/16" and I normally use 1/2" in an 8" shell for a pistil. Plus I needed to make more .

 

Enjoy.

 

http://www.apcforum.net/files/8_Red2BlueChrys.wmv

[ewest]

Man Ravaz, you're stuff always looks awesome. btw, how do you get that streamer from the back of the shell as it's launched? do you use spoolettes for time fuses?

 

I made my first 3" shells this past weekend and I'm just using Chinese time fuse and you don't see the shell after it's launched until it ignites.

[Mumbles]

You attach a comet to the shell. Even spoolettes wouldn't make a tail that large from my experience. The comet is lit by the lift charge. Usually I run the leader over the comet with the quickmatch cut away to spray some fire on the comet to light it.

[ravaz]

Just like Mumbles said, attach the comet to the shell. My method is as follows:

 

I take a piece of gummed tape twice the width of the comet and enough for 3 turns around it and wet both sides with water. I leave about 1/4" or 1/8" exposted on the top, and the rest hangs off. I then let it dry for a few minutes in the sun. Once it's dry, I take a sharp scissor and cut tabs on the paper that's hanging off. Next I'll wet it with some water or wheat paste. Next, use some hot glue and put it on the comet itself and attach it to the shell. Finally, I take the paper that we cut tabs in and attach it to the shell with some wheat paste. I use a piece of wood or metal rod to smooth the paper down on the shell. Let it dry for a few hours. Sometimes I'll use Elmers glue also.

[ewest]

You just put the comet on the bottom of the shell close to the time fuse right? And the gummed kraft tape helps the comet not get crushed by the lift charge I take it?

 

In all the tutorials on shell construction I don't think I've seen that mentioned before, and I was wondering how that was done. Not only does it make for a really nice effect, but it also helps you spot the shell just before ignition. When you're trying to film the shell, it's very hard to determine where it is in the sky without a tail.

 

Neat trick, I'll try that next time. Thanks.

[ravaz]

No, this goes on the top angled a bit to the side. The time fuse is on the bottom, this is more towards the loop of string on the top of the shell. I'll take some pictures and show ya.

[hashashan]

how does the lift charge light it if its on top?

[ravaz]

The flame from the lift charge is more then enough to light a comet ontop of shell. It's more then enough to light smaller shells I attach to my shells.

 

If you pause the video when the shell comes out of the gun, you will see a flame come out of the mortar.

[psymon]

It isnt really proper pyro to use bought BP. I mean its almost like going out and buying a firework and saying its yours.

I was given loads of hassle on another forum when I said I used a little bit of a military flare to make my red fire. I have access to plenty of military flares, parachute rockets and orange smokes. Sometimes I will crack one open and use a little of the strontium based red to save time and a bit of money, but i wouldnt say that its a proper hand made device. It also works well to ignite thermite mixtures.

 

So far for my shells I have only ever used mixtures I made myself. The military flare mix is really difficult to light and is useless when you try to prime it. So for now I will make everything myself and only use a bit of the flare stuff if i really want to get something burning quick...

[Mephistos Minion]

I mainly dont like the use of commercial BP as I cant afford or obtain it

 

Ok, sorry for a seemingly easy question, but what height is good for a 3" canister shell, single break. I looked on passfire with dimensions for paper, but they used pronumerals, and I cannot find any articles with a 3" shell in them.

[Mumbles]

2.5 to 3.5" tall is the standard height. I usually tend to go on the higher side of things myself. Any length will work though. I've seen shells up to 10" long.

 

The gummed craft mostly just helps to adhere the comet to the shell. I have seen comets on the bottom, but the top is much prefered to stop it from being crushed by the lift. As I mentioned before, it also allows the leader to be ran over it if you wish.

[ewest]

Oh, ok. So the quickmatch comes down, through the loop on top of the shell (string or plastic eye depending on what you're using). Across the top of the comet to light it just in case the lift doesn't. Then down around the bottom of the shell and into the lift cup.

 

And I don't think using commercial BP is cheating any more than buying pre-rolled tubes is cheating. Besides, "If you really want to make something from scratch, you'd have to first create the universe" -Carl Sagan

 

I do make my own Meal-D, but I use commercial for lift. It's just easier for me because my most precious commodity is time.