Lift charge for shells

[viziers]

OK i figured i start a new thread on the amounts of lift charges people use in various shells to help new people starting out in pyro like myself and others as in say you have a 3" shell and it weighs ohh 250 grams how much lift charge in grams did you use to launch it, was the charge home made or commercial and was the shell a tight fit or not and how high do you estimate it went up in the air.. If you can post your info in the following way below that would be good..

 

 

Type of shell Sphere/Cylinder - ?

Shell size - ?

Shell weight - ?

Wrapped or Unwrapped - ?

Tight or Loose fit in mortar - ?

Lift charge Home made or Commercial - ?

Amount of charge in grams - ?

Height of shell in air - ?

 

I figured this could help new and veterans alike.

 

viziers

[FrankRizzo]

While this is a good idea in theory, you'll find that there are way too many variables present in powder alone to make this information usable. It's best to just use the "ounce per pound" rule on a test shell, and adjust your lift amounts accordingly.

[viziers]

I know there are many variables thats why this would be a informational topic and not an exact science type of topic. Granted i have been reading as much infoas i can i just figured this might prevent a very new person from using 6 times as much as really needed and hurting themselves or anyone else.

[al93535]

I agree with frank you need to test a dummy shell.

 

But here are my specs:

 

Type of shell Sphere/Cylinder - ball

Shell size - 6"

Shell weight - 1600 grams

Wrapped or Unwrapped - What does this mean?

Tight or Loose fit in mortar - Neither, there is about 3/32" clearance

Lift charge Home made or Commercial - homemade

Amount of charge in grams - 106 grams

ADDED IN- grain size of lift - 6-12 mesh

Height of shell in air - 600-700 feet

 

Type of shell Sphere/Cylinder - Ball

Shell size - 4"

Shell weight - 360 grams

Wrapped or Unwrapped - ?

Tight or Loose fit in mortar - same as above

Lift charge Home made or Commercial - homemade

Amount of charge in grams - 24 grams

ADDED in - grain size of lift - 12-16 mesh

Height of shell in air - 400 feet

 

As you can see I use 1/15th the weight of my shell in powder. However, on a few recent shells that are unfired as of yet I have used 1/16th.

 

A good starting point is to use 1/16th for commercial, and about 1/14th for homemade if you believe your lift is good, 1/12 if its not so hot, and about 1/10 if it sucks. Make yourself a dummy shell, time it and figure the height, then adjust your lift accordingly.

 

Also grain size is important, thats why I added it in. I use 6-12 mesh for any shells 5" and bigger, OR a 4" shell thats quite large. and 12-16 mesh for 4" and smaller shells.

[d4j0n]

I think some important variables are the corning method (pucks? dextrin+bp+sieve?) and method of making the homemade bp (mill time, charcoal type, pressing).

[TheSidewinder]

Good info here.

 

My 3" shell I have in the competition forum weighed within a few grams of 1/2 pound, and so did the other two I shot that night, but it took considerably more than 1/2 an ounce (14 grams) to lift it. I had to use 20-22 grams. I'm using commercial Goex 2Fg Rifle Powder, too.

 

It's a balancing act. I'm still learning, but I think I'm starting to get the hang of it.

 

M

[viziers]

I was doing some research on lift charge types of commercial grade powders and have noticed that they reccomend (sp) that you use 2FA which is the equivelent of cannon grade sporting powder or 1FG. Is this correct to anyones knowledge? If noe please advise differently please.

[Mumbles]

Yep, 2FA is the standard. From a size point of view, Cannon of Fg are the same. However, they have different compositions. FA is not glazed, and it will probably burn faster than the Fg. FA is blasting powder, so you want more of a shock. Cannon and Fg are sporting powders, so they will have a slower burn for a more propulsive.

[viziers]

Yep, 2FA is the standard. From a size point of view, Cannon of Fg are the same. However, they have different compositions. FA is not glazed, and it will probably burn faster than the Fg. FA is blasting powder, so you want more of a shock. Cannon and Fg are sporting powders, so they will have a slower burn for a more propulsive.

SO mumbles i should be ok with using 1FG for lift powder... I know your gonna say search and say didn't you read what i wrote but sometimes i need perfect clarity on things before i do or use somthing i guess i'm just a little over cautious when it comes to things of this nature.. Sorry for the ramble.

[Mumbles]

Go ahead. I've heard of people using 2Fg without a problem. I'm a cheapass so I use homemade stuff personally, but there is no reason why 1Fg won't work.

[viziers]

Go ahead. I've heard of people using 2Fg without a problem. I'm a cheapass so I use homemade stuff personally, but there is no reason why 1Fg won't work.

Cheapa**?? umm mumbles if you have 2100 pounds of stuff id say your anything but a cheapa**.... the thing is id guess if i do use the 1FG id have to use more of it than say if i used 2 or 3FG would this assumption be correct??

 

Thanks for your time and advice Mumbles!

[Mumbles]

Yeah, but I resell a lot of those chems.

 

My best advice would be to just experiment with what works correctly. There arn't really values out there for 2 or 3Fg, so there isn't really a problem there. I would start with the standard 1oz/pound, and go from there until you are happy. 3Fg would be too fine for anything but lifting cake inserts I would think.

 

Cannon is nearly the same meshwise as 2FA. 1Fg is smaller, so you may be able to get away with using less of it.

[asilentbob]

I was under the impression that cannon and 1Fg were considered good for lift. I thought cannon had smaller mesh values that 1Fg and hence bigger grains.

 

I could have sworn i bookmarked a link.

Ah Ha!

 

Skylighter bullitin

 

Under:

"* Size Does Matter—Black Powder Grain Size"

 

Ok, i see, i keep getting mixed up when people say cannon grade and 2FA.

[FrankRizzo]

Well, you *can* use 2fg for lifting shells up to 6" in size, there've been a few articles in AFN about it. But, it's not only expensive to use sporting power, but your shells have to be constructed very well to withstand the hammering. Pasted paper shells will be more likely to survive versus un-pasted plastic.

[TheSidewinder]

I'm using commercial (Goex) 2Fg to lift my 3 and 4 inch cannister shells, and 4Fg to break them. The video I posted in the competition section shows the lift. It's a good sharp POP. The break is sharp, but not as sharp as whistle or flash bursts.

 

The only reason I'm using these 2 powders is because I have had a few pounds of it sitting in my garage gathering dust for almost 20 years. Once it's gone I'll be switching to 2FA for lift, and 4FA (or whistle, slow flash, etc) for break. And since I have 20 lbs of softwood charcoal on its way to me, I'll be making my own. Woohoo!

 

M

[millhouse]

Remember that the quality of BP differs realy much of what type C you use!So even if you say 2Fg it doesnt mean your BP is good enough

[FrankRizzo]

Remember that the quality of BP differs realy much of what type C you use!So even if you say 2Fg it doesnt mean your BP is good enough

Very true, the charcoal plays an extremely important role. When people say 2fg, 2FA, etc., that usually implies a commercial product which should have good consistency from lot to lot...you don't worry about which charcoal was used to manufacture it.

 

While you can sieve a homemade powder to approximate the grain size of commercial product, it's still *homemade* powder. You should make a few large batches, combining all of them together, in an amount that will last you through the season. Dummy shell testing will determine the amounts of *your* powder that work the way you to want them to. Consistency is the key.

[viziers]

Thank you all. The information is very helpful i have currently made a 3" shell filled with doggy food and have "pasted it with paper adhesive mailing tape so that the shell has a 1/8" space around it if its sitting in the tube as appose to almost a 1/4" space if the shell has no wrappings on it.. Is 1/8" to loose a fit to lift it? Does this make sense to the people who are reading this??

 

One other rambling question a little off topic. If i wrap craft paperin a tube with regular visco fuse inside it will it speed the burn rate.. I would assume it would but wanted to ask before i wasted fuse.

 

And if i coould get suggestions on types of materials you use for wrapping the outside of the plastic shells to create a tighter fit in the tube and what is the best to use which will bulk the shell width to create a snug fit in the tube keeping in mind asthetics "looks" of the shell.

[Mumbles]

That gap should be fine

 

Visco in a paper tube doesn't increase the burn rate, or at least shouldn't.

 

As far as wrapping, I follow a proceedure very similar to paper shells. I use any strapping tape I will directly on the plastic. Then I add a layer of masking tape. Then I paste normally, though less layers, with paper. The masking tape gives the paste a rougher surface to adhere to. I've found that the paper sometimes slides around when it is directly applied ot the plastic. Please continue this conversation of pasting and bulking of shells in the aerial shells thread, or pasting thread if we have one.

[viziers]

That gap should be fine

 

Visco in a paper tube doesn't increase the burn rate, or at least shouldn't.

 

As far as wrapping, I follow a proceedure very similar to paper shells. I use any strapping tape I will directly on the plastic. Then I add a layer of masking tape. Then I paste normally, though less layers, with paper. The masking tape gives the paste a rougher surface to adhere to. I've found that the paper sometimes slides around when it is directly applied ot the plastic. Please continue this conversation of pasting and bulking of shells in the aerial shells thread, or pasting thread if we have one.

Thank you Mumbles sorry for the taping ? i didn't expect the elaborate answer but it still is appreciated.

[viziers]

Well today i completed my 3" test shell with a 1/8" gap of space around it when its in the tube and the shell weighs 90 grams and have put 10.5 grams of 1FG commercial powder as my lift charge. Does anyone have any speculations as to what the outcome will be weather it will go 50ft high in the air and so on. I will hopefully launch the shell on Wednesday and will post the outcome of the test.

 

thanks for your input.

[justanotherpyro]

Tonight I found out that pressed powder is extraordinarily good, and that grain size doesn't matter as much as I thought it did. I shot a 325g 4" shell with 32.5 g of lift. It was snug in the mortar but slid down the mortar with its own weight. It was WAY to much. I'm thinking maybe around 20 g for other 4"ers this general weight.

 

The lift powder was at leat 50% fines, and had granules that would easily pass through my kitchen strainer.

[viziers]

Well i was finally able to shoot the test shell and id say it had a height og roughly 200 ft whis is ok i guess wish it went a little higher but i guess i could of either used a little more lift powder or made the shell little tighter of a fit in the tube either one would of worked i guess. all in all i was pretty happy with the results but the real test will be of the fireing of a live shell.

[keepkool79]

I do not have time to make up anymore bp before the 4th so I plan to use some fg powder. What would be my best bet, fg or ffg? I am lifting shells 4,5,6 round plastic and some 4 inch canister shells, 3 of which are salutes. Please let me know ASAP.

Thanks for the help,

[al93535]

Fg would be best.