What type of blackpowder to add to AT reloads for ejection charge?

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ascastil

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Can I just go down to Cabelas and buy a little thing of black powder for rifles or something? I didnt come up with much on a search, just found out to add more. Dont want my Gforce turning into a lawn dart again. Thanks.
 
What works best and is used by most is Goex 4F. Some say 3F works just as well. I would avoid Pyrodex but others may argue.
Also, probably not best to tell the store you buy it at that it's for rockets.
Usually motor vendors at launch sites sell the real Goes 4F.
 
If you have a local gun store, try to find some FFFF black powder.
 
Can I just go down to Cabelas and buy a little thing of black powder for rifles or something? I didnt come up with much on a search, just found out to add more. Dont want my Gforce turning into a lawn dart again. Thanks.

4Fg is recommended, however 3Fg is more common and more readily available than 4Fg ( aka FFFFg). Cabelas may have one or both types, 4F is used for priming flintlocks, and 3F is used for the main charges in BP firearms. Do not get a black powder subsitute such as Pyrodex, Triple Seven (777) while they can be made to work, real BP is easier and more reliable for our uses.
 
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One alternative is to buy 5lbs. or more by mail. Have to pay hazmat but doable if several fliers go in on an order. I've seen some real pretty Swiss 4F out there that works mighty fine. Kurt
 
Where ever you go, do NOT tell them it's for a rocket.

You'll be sending postcards home from Guantanamo bay.
 
Last time I bought mine it was from a Bass Pro Shop and then ended up carrying it around the mall attached to it for the next couple of hours. That seemed really strange.......
 
Last time I bought mine it was from a Bass Pro Shop and then ended up carrying it around the mall attached to it for the next couple of hours. That seemed really strange.......

Last time I bought some it was for a cannon. I told the guy it was for a cannon. We used it in a cannon, at a wake. CANNON.
 
We normally call it 4f but like Rich says, it will actually say FFFFg on the can. 3f (FFFg) will work, but if you have to buy some just for rocketry, opt for 4f if it is available. The more 'F's, the smaller the grains; the smaller the grains the more energetic the burn. Generally the smaller amount you need, the smaller grain you will use. 4f should never be used in a cannon lol, unless its a small cannon.

And yes, if asked tell them it is for a muzzleloader. If you have to be specific: a .32 caliber pistol or the flash pan on your flintlock that you got as an early Christmas present.

You could also extend you motor mount up to reduce volume to be pressurized, aka a stuffer tube.
 
We normally call it 4f but like Rich says, it will actually say FFFFg on the can. 3f (FFFg) will work, but if you have to buy some just for rocketry, opt for 4f if it is available. The more 'F's, the smaller the grains; the smaller the grains the more energetic the burn. Generally the smaller amount you need, the smaller grain you will use. 4f should never be used in a cannon lol, unless its a small cannon.

And yes, if asked tell them it is for a muzzleloader. If you have to be specific: a .32 caliber pistol or the flash pan on your flintlock that you got as an early Christmas present.

You could also extend you motor mount up to reduce volume to be pressurized, aka a stuffer tube.

It was a fairly small cannon, designed for golf balls. We used tinfoil for the projectile.

They sell pocket cannons for about fifty which take wrist rocket bearings, which helps the cannon story be absolutely true.
 
It was a fairly small cannon, designed for golf balls. We used tinfoil for the projectile.

They sell pocket cannons for about fifty which take wrist rocket bearings, which helps the cannon story be absolutely true.

Awesome. Cannons are cool no matter how small. We got my dad a small "Old Ironsides" in .68. It is supposed to use 2f but we probably will use some of my 3f, just smaller doses. I use 3f in my 50 cal rifle all the time, and it is supposed to use 2f as well.
 
My preferred fib (not yet used) is "My [uncle/nephew/cousin/buddy, choose one that suits your age] is taking me black powder shooting. He told me to buy some 4F to take along." If you give them too much info, they might start asking inconvenient questions like "I love .32 black powder rifles! Which one do you have?!" The key to anonymity is to appear friendly but not too bright. I call it the Golden Retriever rule. :)
 
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You gotta play with them. Run around so you're sweaty, wear a black hoodie and mutter to yourself, things like "they'll see" or "sheep, all sheep"
 
But what if my friend really is building a cannon? And, last time I stopped in for FFFFg, the gun store did actually have cannon fuse.
 
I did some looking on the Cabelas site and it looks like they only have Pyrodex. What is the weak point of this stuff? Will it help any if thats all I can find? Ill keep looking and go down there and take a look. Id really hate to have to order some and pay hazmat.
 
Do you have a motor vendor at your club/launch? They just about always sell the real BP.
 
Ok guys, I went ahead and ordered a 12 pack of ejection charges from Aerotech. It was 20 bucks shipped so Ill just order it from them until I figure something out.
 
I did some looking on the Cabelas site and it looks like they only have Pyrodex. What is the weak point of this stuff? Will it help any if thats all I can find? Ill keep looking and go down there and take a look. Id really hate to have to order some and pay hazmat.

Pyrodex needs tighter containment than black powder to get the same sort of fast burning that produces the gasses needed for an ejection charge. It can be done, but isn't the best product.

Here is an older test of pyrodex in some ejection canisters: https://pratt-hobbies.com/info_pages/pyrodex/pyrotest.htm


kj
 
Part 2 of my thead I guess should be how much extra powder should I add so my Gforce will eject a parachute? Should I add some extra just in case to all my rockets, an Initiator and Strong Arm? Can there be too much?
 
I bought my BP from a gun store, told them it was for the ejection charge for EX rocket engine. Sure no problem. Sold me 1lb. of 4F BP.

You gotta play with them. Run around so you're sweaty, wear a black hoodie and mutter to yourself, things like "they'll see" or "sheep, all sheep"
Oh boy...
 
Part 2 of my thead I guess should be how much extra powder should I add so my Gforce will eject a parachute? Should I add some extra just in case to all my rockets, an Initiator and Strong Arm? Can there be too much?

What type of motors are you putting in your GForce? I lawn darted my GForce on its maiden flight because the coupler was too tight. That was when I first started in mid power and didn't get the coupler sanded aggressively to provide a smooth and easy separation. I salvaged the booster and rebuilt the rest of the rocket. I have launched it since then 15 or so times on AT G's and never had a problem, or had to add more powder.
 
G64. The coupler was pretty loose. I could pick it up and its own weight would make it slide apart. I also salvaged a bunch of parts and ordered new ones to rebuild it. That was the maiden voyage and I dont want it happening again.
 

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