black powder competition

[Potassiumchlorate]

Interesting. I have used 7-10% of the shell weight with a mix of FA and 2FA with a density of 1.7g/cc, but they seem too weak for lifting the smaller shells, although the BP itself is pretty "hot". I recently made 4FA grains instead, but they might on the other hand be too fine for 5" and 6", right?

 

I just must test 5/1 on rice hulls.

[Mumbles]

2FA in my experience is too coarse for small shells. I use 4FA on shells 3" and smaller, and most mines. I'd probably use it on 4" ball shells too just to be safe, but that is kind of a toss up. Much larger than that and you start really launching shells. I fired a 6" shell once with a normal amount of lift using commercial 4FA, and it was still well on it's way up when it broke. I thought I busted the gun it lifted so hard. You can use 4FA to lift larger shells, but you need to use less of it. a 6" shell probably weighs between 1100 and 1300g depending on what's inside. This would require somewhere around 75g of lift. Using 4FA will shoot it into orbit at that amount if you truly have hot powder. You could probably dial it back to around 60g or less. There may be some tables in some of the Best of AFN books.

 

The product I use for lift from my homemade powder is 2+3FA. I use a wider range than is normally used commercially. My meal is plenty hot on it's own, but inclusion of some of the finer stuff helps to break my shells a little better. I lift all of my shells as normal and they still work fine without lifting too overly hard.

[Potassiumchlorate]

So 5% of the shell weight of 4FA would lift a 6"? That's about what I thought, though I was uncertain if it was possible or not without breaking the shell.

[bob]

if using grass seed in a 5 to 1 ratio each seed should have .05 grains of black powder coated on to it

bob

 

 

 

[Potassiumchlorate]

How small mortars can BP on rice hulls be used in? It didn't work in a 16mm stargun. Just said "pooff!" and the star went one meter or so.

[californiapyro]

i've used it with a 12 mm stargun... i guess it depends on the amount of BP on your hulls

[Potassiumchlorate]

Hm, but now I have 5:1 on rice hulls. Weird. Must test some more.

[Potassiumchlorate]

*Sighs*

 

I tried again. Very long muzzle flame, but still "whoof" and not "bang". But maybe it should be that way with so small amounts (1.5g)? The star didn't seem to ignite this time, or, if it did, it burned too fast for me to notice. It's daytime here, so it's hard to decide.

[Peret]

Describing powders by FA grades is as traditional and pointless as describing rockets by weight - the more so since only a handful of people have access to FA grades anyway, and the sizes of FG grades are entirely different. Why not keep it in mesh sizes? I lift with 10-20 mesh mostly.

 

While the quality of a particular powder is important, I found it was more important to keep the lift charge confined, especially for small shells. It does take some finite time for the fire to propagate from grain to grain, and anything that doesn't ignite in the first milliseconds is wasted in a short mortar. 10 grams twisted tightly in a baggie will give a far better performance than 10g spread over the bottom of a mortar tube. My objection to using coated hulls would be that they're very bulky and can't be so well confined.

[Mumbles]

Another concern I'd have with using rice hulls to lift shells would be club shoots. At the clubs I generally attend, we have shared guns that are used repeatedly. If I were to bring half a dozen 6" shells with 90g of 7:1 as lift, by the time I fired them, there would already be more than an inch of rice hulls remaining on the bottom. I've ran into problems before with people using paper or plastic cups as lift cups and other things that are left behind. When there gets to be a little padding on the bottom of the gun I've started to experience lower breaks.

[mikeee]

Everyone,

 

Another good way to test black powder is to "shoot anvils".

You need (2) high quality forged steel anvils.

One anvil has a hole drilled into the center of the flat top.

A measured amount of black powder is loaded into the drill hole.

A playing card is placed over the black powder and a small diameter fuse ran to the outside edge of the anvil.

The other anvil is turned upside down on top of the other anvil.

Fuse is lit and powder ignites and propels anvil into the air.

Total energy of black powder is measured by the total distance anvil travels up in the air.

An old time military guy told me this was how they tested black powder in the civil war era.

Back in those days quality of black powder was an issue for the artillery groups.

If you wanted to hit your target you needed to know how "hot" the black powder was.

[Peret]

I've seen anvil shooting at Winter Blast. They go straight up a couple hundred feet and land next to where they took off. I wouldn't care to hand-light one in case I tripped running away.

[Potassiumchlorate]

Haha, anvil shooting is so American. Shooting something in the air that was never intended to be airborne.

[Potassiumchlorate]

Now I've tested BP on rice hulls as lift for a 2" dummy. Quite different performance. About as good as my corned BP.

[Potassiumchlorate]

Hm, now I have tested "baseball shooting" or what you call it in America. A tennisball, weighing 52 grams, was shot from my 3" mortar with 5 grams of my new BP. No liftcup, just BP on the bottom of the mortar. Ignition by visco+quickmatch. The ball was shot about 30 meters up in the air (I compared with a tree nearby) and reached its apogeum after about 3 seconds. How would you "rank" this?

[Potassiumchlorate]

*BUMP*

 

I think von Maltitz is wrong with this thing about getting a better BP when not compressing, at least if you have really good charcoal. I still find the compressed BP superior, although it isn't bad with "pulverone" either, and it's much less work to make.

[bob]

Not sure if I should be posting this here but I think it's ok. Anyway I think I have a new (well at least it's new to me) way of testing black powder.

what I did is I took a piece of pipe and pluged it and drilled a 1/8 inch fuse hole, after being pluged it is 19 inches long and 40.3 mm ID. Then I took a 39.7 mm OD ping pong ball that weighs 2.8 grams. Then I mounted the pipe on a wood plate form so that the mortar is at a 60 degree angle. fused it with black match and loaded it with 3 grams of 17 mesh black powder and the ping pong ball, and lite it. Then when it lands I simple take a measuring tape and measur how far it went(remeber I mounted it at a angle). When I did it today it went 70 feet, did it again and it went 80 feet. I know ten feet is a big differents but there was a lof of veritbale, I'll do it again soon and cut down on a lot of the veritables and see how close I can get them landing.

Well what I like about it is you don;t need much space; it doesn't make much for noise at all yeah I know thats a pro and a con; it doesn't take much bp to shoot; ping pong balls are cheap; because it doesn't go very far it's quite unlikly that you'll loose the ball; and if the ball does hit somthing it's so light it will not do anything. Of course it does have cons like if theres any wind it kind of wrecks it as far as tests go; and I can't see it being the most accurate test.

anyway just thought I'd share it with you.

Adam

[bonkers]

Ping pong balls are way to influenced by the wind conditions, i would think golf balls in a normalized mortar would get better results.

[yvariro]

hi all,

If here we post video of our BP, I post a video of mine,

 

Before the video,the ratio is 75/15/10,milled for 24H(i have a little ball mill ),the charcoal used is pine,and the bp was granulated through a kitchen screen,4mesh a think.

As you can see it remain small residues but this is not bad because i don't have shell ignitions problems

 

http://www.youtube.com/watch?v=Lw8fhrq-Msc

[pyrogeorge]

My BP for 1hour milled!

Edited February 4, 2013 by pyrogeorge

[Potassiumchlorate]

Nice, George. I always like your stuff

[pyrogeorge]

Thanks Potassiumchlorate!

[vegasdude]

Here is mine made for Paulownia from Algenco...

 

http://youtu.be/1k7oXuDJpJY

[DanielC]

The golf ball or baseball test works great except for when you lose sight of it and need to run for the nearest trees. On his website, Danny Creagan did his testing on a 3 ft piece of basically perforated angle iron with 2.5 ft. in between measuring posts. We use them sometimes to mount electrical conduit on walls and ceilings for industrial applications. The powder was about 1/4" tall in the groove. So that would be about 1/2" wide x 1/4" deep. I really enjoyed the charcoal test results and still have a copy of it in my workbook. If you haven't looked them over, you probably should check them out. That being said, I still have lots of old golf range balls that need a fitting farewell. Luckily I have no close neighbors.

[Bobosan]

I put together a short version of Dan's test chronograph using the angle iron and triggered it to time a 12" burn via a stopwatch. I'm not sure anymore which thread it's in but somewhere here in the APC forums there are videos of some burn tests.