Lift powder 4 inch shell

[Wiley]

Rocketier, according to Fulcanelli, pulverone is KNO3, charcoal, sulfur, and dextrin, mixed by passing through a screen. It is then wet into a ball and granulated through a (usually) 4 mesh screen.

 

If I mill my nitrate, sulfur, charcoal and dextrin together for an appropriate amount of time in a properly optimized mill and granulate it by rubbing a wet ball of it through a screen, I most definitely get BP, and very good BP at that. This is what most of the pyros I know are doing to make BP. I myself have never corned it, which is what what I believe you are describing, and I never intend to, since it's just more work for the same product. In Merlin's case, simple granulation through a screen will be more than adequate.

[Mumbles]

There is some ambiguity to the term polverone/pulverone. About the only thing that is agreed upon is that it is granulated in some manner. I use it to refer to an unmilled mixture that acts as a flammable filler and packing material. There are some who also use it to mean a milled mixture, and holding to the definition that true black powder must be milled and corned. The uncertainty seems to result from a mixture of regional terminology and misinformation from lower crediblity sources.

[Merlin]

Last night I began to suspect the charcoal as many of you have. I didnt want to blame the charcoal because it is hard to get good charcoal unless you make it yourself. I had been struggling with commercial airfloat then located custom charcoals willow. It looked good, it ground up good and why wouldn't it be good. It might be- but not as is. Last year I decided to mill dextrin in with my BP. What came out was marbles to golf balls and very hard. I decided I would not do that again and tossed it. Fact is the willow has water in it. I just milled a batch for 24 hours and the burn test was slow (0.8 sec.) by Wiley's test. What I don't understand is what difference it makes if the finished meal has moisture in it? The burn test is a good indicator of when the milling process is complete provided it is all dry. But after 24 hours I think everyone would agree the milling should be complete with good milling. But the meal will fail the speed test if it is moist. What I dont understand is why it matters if you are going to screen in dextrin and add more water to granulate? It is true unless I have a dry mill comp I cant be sure when the milling is finished so the end product is hit or miss mostly miss. I would expect this batch to perform well once it is granulated and dried. If not, provided it is granulated and dried properly then I must suspect that the charcoal is not really a type suitable for pyro at all. This has gone on since last year for me which is why I gave up and went to benzo but maybe with the forums help it will be resolved this time. I will granulate, dry and test and post the results. I am getting a totally different charcoal from Woody's general store that is pyro grade for the next milling attempt. I am beginning to see why everyone makes their own. Thanks for all your help. I am not sure my charcoal is totally unusable but it is causing the problem. That's a step in the right direction. I wonder how many beginners quit because of the fine art of BP?

[Rocketier]

I know most pyro's just make unpressed pulverone. I do that too but there is a difference in result. When you lift with pulverone the sound is louder than when you use bp. Bp results a deeper bang and more gasses are produced in shorter time. This because of the higher density.

 

Pressing bp result in a more stable product. 1,89gr/cm3 is the most optimum to where you can press it to. I make pucks about 10cm width and 1cm high. The I break it and put it thru serveral sieves. The small particals will be repressed while they are still wet.

 

A long time ago Dan Williams made a nice tutorial for making pressed bp. Link to that tut

 

 

link to wiki full document

 

 

Corning

For gunpowder to explode effectively, the combustible ingredients must be reduced to the smallest possible particle sizes, and be as thoroughly mixed as possible. Once mixed, however, for better results in a gun, makers discovered that the final product should be in the form of individual dense grains that spread the fire quickly from grain to grain, much as straw or twigs catch fire more quickly than a pile of sawdust.

Primarily for safety reasons, size reduction and mixing is done while the ingredients are damp, usually with water. After 1800, instead of forming grains by hand or with sieves, the damp mill-cake was pressed in molds to increase its density and extract the liquid, forming press-cake. The pressing took varying amounts of time, depending on conditions such as atmospheric humidity. The hard, dense product was broken again into tiny pieces, which were separated with sieves to produce a uniform product for each purpose: coarse powders for cannons, finer grained powders for muskets, and the finest for small hand guns and priming.^[99] Inappropriately fine-grained powder often caused cannons to burst before the projectile could move down the barrel, due to the high initial spike in pressure.^[100]Mammoth powder with large grains, made for Rodman's 15-inch cannon, reduced the pressure to only 20 percent as high as ordinary cannon powder would have produced.^[101]

In the mid-nineteenth century, measurements were made determining that the burning rate within a grain of black powder (or a tightly packed mass) is about 0.20 fps, while the rate of ignition propagation from grain to grain is around 30 fps, over two orders of magnitude faster.^[99]

 

Edited May 23, 2015 by Rocketier

[Wiley]

You're probably right, Rocketier. But for me, my un-corned BP is just as good or better than Goex, which is corned but made with crappy charcoal. Whatever works

[braddsn]

Merlin: To answer the question at the end of your last post, we don't quit!! That is what makes us 'pyros'. I have had many setbacks, and have banged my head against the wall hundreds of times. The challenge is what keeps my head in the game. Pyro certainly isn't for the faint of heart. But the more you do it, the more you learn. Shoot for nothing less than perfection, and you will get there. I still say moisture is your issue. 'Most' pyro's that I communicate with, including myself, mill WITH the dextrin. I make in the neighborhood of 3kg per week and the dex has never caused a problem. The fact that you said you got large rock-hard pieces when you milled with dextrin just tells me again that moisture is your issue. That dextrin was activated in your mill. IF any of the ingredients you are milling aren't totally dry, your powder will fail the burn test. As you probably know, I shoot a LOT of shells for testing purposes. Probably 10-15 per week. And I can remember 3 different testing sessions in the past where I went out to test, and ended up dodging stars because the shells only lifted to about 80 ft. After the 3rd said mishap, I finally figured it out. It was moisture. I took the bp that barely lifted the shells, and set it back out on kraft paper for a few days. Then went out and tried it again.. and BAM.... shells were hitting 350 ft no problem. Simple case of the bp being about 90% dry, but not 100%. Live and learn. You will figure this out in short order, then look back and laugh at it. On you go!

[Arthur]

My experiences with BP were that the problem is usually with the charcoal.

1/ use a choice wood -Willow or Alder are my local choices. You may have local woods that are good.

2/ use soft charcoal -if you need a tool to break the lumps it's a bad sign. The fastest powder came from pieces almost to fragile to lift.

3/ Use dry charcoal - Charcoal lumps can adsorb their own weight of moisture so your mixture is wrong when you weigh it.

 

It's not uncommon for commercial powder to be five years old when bought and then stored part used for another few years, -dry storage doesn't harm commercial powder kept in it's original container.

 

If you mill (say) 500g of charcoal,of each of several woods then the largest volume of product will make the best powder.

[Merlin]

Update- I ball milled for 24 hours to make sure it was not the milling time. Granulated with dextrin, dried overnight at 120 degrees at 17% humidity in a forced air drying box. Same as before- 25 grams of the Bp sent a baseball 180 feet up. I am totally convinced it is the charcoal. My willow supply may not even be willow from custom charcoal.

Getting 3 lbs from Caleb to try. Also, since i only need small quantities I am get sealable gallon paint cans from Lowes. I have a good gas burner. I will cut up either white pine, spruce or use cedar shavings, seal in can with small hole in top and when the smoke clears light the gases emitted from the hole and when flame goes out allow to cool and then make airfloat. I have seen set ups with a 55 gal drum and a 33 gal sealed drum inside with a fire under the 33 gal. But will not the gallon can also work?

Edited May 24, 2015 by Merlin

[Arthur]

Charcoal is one of the small components it's 15% of BP, Get good stuff and be sure what it is and that it is dry before you weigh it. Learn which of your locally available woods make good charcoal. In the UK it's willow or alder for BP and pine for spark effects.

 

 

Is a vid from the UK of someone making charcoal economically

[Shunt]

Merlin I see you live in Alabama, I am a bit north of you in Tennessee.

 

The best charcoal I have made to date from local trees came from Staghorn Sumac. Here is a link for more information.

 

http://www.eattheweeds.com/sumac-more-than-just-native-lemonade/

 

If you can find this in 'bama, I highly recomend it. It grows very fast, almost like a weed. I cooked my first batch of pyro charcoal out of this in a stainless steel meatloaf pan covered with 3 layers of heavy aluminum foil on my gas grill. Took some time and used a lot of propane, there are much more efficient ways to do it, but it made the best BP I have ever made.

 

I have since gone to tulip poplar, and cedar pet bedding from the local stores as it takes less time to make.

 

Get a gallon paint can, punch 3 holes about 1/4" around the top, load it with cedar pet bedding, cook till the gases no longer take fire, then another 15-30 minutes depending on how hot your fire was, take it out of the fire and turn it upside down and mash it into sand/dirt/ or cover the holes with AL duct tape so no air can get inside and continue the burn process and create ash.

[Merlin]

Shunt, good to know someone in the area!

I had no idea Sumac could be used. It grows all over even on my property. Do you harvest green or wait til winter? I have some red alder on way from calebkessinger. Also, I am going to try the red cedar pet bedding. My willow from custom charcoal is very hard has to be broke in a bucket with a sledge then ground and milled. I may try recooking in the paint can at some point just to see as I have a lot on hand. For whatever reason it makes very poor BP. The alder and red cedar should do the trick now I know how to make it. I plan to use a propane burner, the kind used for seafood boils. Put out quite a lot of heat less you cut it down low. Thanks for the post.

[FlaMtnBkr]

Check out the TLUD cookers as all you do is light the wood on fire in the can and it's like a little self contained camp fire and does not need an external heat source such as a propane cooker. It is also self regulating so when the flame reaches the bottom and is about to go out you shut it down and close it up to keep oxygen from getting in and the charcoal burning to ash. You don't have to worry about over or under cooking as with a retort and should produce consistent results from batch to batch. The pet bedding chips also cook easier than a retort where the charcoal produced first along the outside of the can insulates the wood in the center which then doesn't cook fully unless stirred. A retort can also gets a lot hotter and burns out after a dozen or two cooks.

 

You can make a simple TLUD out of two new paint cans from the hardware store. Maybe someone has links to a previous discussion or tutorial. I know there is some good info with pictures at fireworking.com if you are a member.

 

With that said, it's also nice to have a 1 gallon paint can retort to make charcoal in when you are having a camp fire or even have the wood fireplace going. You pack it full of wood splits and tap the lid on that has a 1/4" hole drilled in it, and use the handle to put in the fire and move around with a stick. Good for smaller batches to test different locally available wood. I have tested just about every tree that is in abundance on my property and found some really good wood for hot charcoal that way. I imagine most pyros like a good camp fire and have a pit or burn barrel in the yard to have one, so might as well make some good charcoal or test a different tree at the same time.

 

Just something to look into and another option.

[Merlin]

Thanks a ton to everyone especially Wiley for the burn test and calebkessenger for the alder charcoal. Thanks also to everyone who encouraged the retort method of making your own. I have milled two batches of meal-D one from caleb (the alder) and one from pet depot- red cedar. Both come in under 0.50 sec on the burn test. Should make good BP when I granulate. Not only was the willow from custom charcoal moist it was not even fully prepared. I put in retort and still got gasses off! No wonder it wouldn't work for BP.

An end to 18 months of frustration. It was the charcoal as many of you suspected.

[braddsn]

Merlin, you might want to consider re-cooking that willow and using it! I had a feeling moisture was playing a part in this. Obviously, it's not good if the charcoal you got wasn't fully cooked, and contained moisture. Glad that you got it under control now. Moving forward!

[Shunt]

Glad you found the problem Merlin!

 

This topic got me to dig out the little bit of BP I had left made with the staghorn sumac charcoal I bragged on in post #13 above and do the burn test Wiley suggested. Guess what... as soon as the visco spitfire hit the powder trail and the powder took fire, I know something was wrong. Probably about 1.2 seconds burn time, and the paper was smouldering after the test. I remember fresh out of the mill it went up in a quick 'poof' and the paper was barely schorced. Same old problem, powder got moist, stored for a year or so in a margarine tub over the winter with no dessicant.

 

I understand the undercooked/moist charcoal was the root of your problem, but thought I would I would add my experience as to storage so you will not have the same problem on down the road.

 

As the oldtimers say...Keep your powder dry!

[Wiley]

Good show! Now we need to see some shells

[Merlin]

BP plenty powerful, granulated 4 mesh with dex/water. Is it necessary to coat rice hulls for lift for a 4" shell or can you use granulated in a lift cup? I thought rice hulls were only used to save weight in very large shells.

My baseball test resulted in a flight time of 11.07 seconds using 22g BP in 3" mortar. Time from the explosion to sound of ball hitting ground as ball was going so fast I could not see it. I am taking 1/3 of the total flight time to calculate approx height of 437 feet. Maybe a bit much for a 3" shell with BP at 15% of shell weight. But I don't have any 4" baseballs so if I put beans in a 4" dummy with this powder do you think about 1oz lift is a place to start?

[nater]

For lift, you can use whatever you want that lifts the shells to a safe height. I know one prominent Pyro who uses BP coated hulls for lift and break to save on a manufacturing step.

[calebkessinger]

With my HOT granulated bp 1 oz. works most of the time.. a few time I thought 1.25 oz. would have been better.

[Wiley]

Merlin, you want around 300 feet for a 3", but I even a little lower usually won't hurt anything. That mostly depends on how your shell breaks. Congrats, by the way! Sounds like you've got yourself some wicked fast power!

[jordanm]

BP plenty powerful, granulated 4 mesh with dex/water. Is it necessary to coat rice hulls for lift for a 4" shell or can you use granulated in a lift cup? I thought rice hulls were only used to save weight in very large shells.

My baseball test resulted in a flight time of 11.07 seconds using 22g BP in 3" mortar. Time from the explosion to sound of ball hitting ground as ball was going so fast I could not see it. I am taking 1/3 of the total flight time to calculate approx height of 437 feet. Maybe a bit much for a 3" shell with BP at 15% of shell weight. But I don't have any 4" baseballs so if I put beans in a 4" dummy with this powder do you think about 1oz lift is a place to start?

I thought that you calculated height by the fall time which is 2/3 of the total flight time so it would be (2/3)*11.07=7.38 seconds of fall time from the apex tothe ground so 16*7.38*7.38 would be a total height of 871 feet. Someone please correct me if i am wrong since i am still learning here too.

[FlaMtnBkr]

I was about to point that out Jordan, and yes, that is the approximation that Ned Gorski has on his website. The shell/ball leaves the mortar very fast and reaches max height quickly. It then slowly picks up speed from a stop and then reaches terminal velocity which is quite a bit slower than max velocity because of air resistance so it takes longer.

 

I would be curious if this approximation holds true for cylinder shells or just spherical objects. My subscription ran out so I can't check what is said. I'm sure there is some difference but it's still probably a reasonable approximation.

[Merlin]

Someone correct me if I am wrong on altitude calculation. There are cal. based on time from mortar to it peeks. and cal. for max height to ground and for total flight time. But it does leave the mortar like a bullet but will actually stop at peak height and then free fall. I read somewhere that free fall time is about 2/3 of total flight time so I subtract that which leaves 1/3 time to max height.

It does not seem reasonable that 22-23 grams of BP could possible send a baseball to a height of 871 feet. A little over 400 seems reasonable and of course you would have to allow for any lateral flight in feet as well. I fire at a slight angle so I don't get hit myself or the house upon return.

[jordanm]

Someone correct me if I am wrong on altitude calculation. There are cal. based on time from mortar to it peeks. and cal. for max height to ground and for total flight time. But it does leave the mortar like a bullet but will actually stop at peak height and then free fall. I read somewhere that free fall time is about 2/3 of total flight time so I subtract that which leaves 1/3 time to max height.

It does not seem reasonable that 22-23 grams of BP could possible send a baseball to a height of 871 feet. A little over 400 seems reasonable and of course you would have to allow for any lateral flight in feet as well. I fire at a slight angle so I don't get hit myself or the house upon return.

It is not out of the question that that much powder could send it that high. It should only take around 15g to get it to 300 feet with the right powder which will equivelate to a fall time of 4.33 seconds. Read this:

http://www.skylighter.com/fireworks/how-to-make/high-powered-black-powder.asp

[Mumbles]

Depending on what value you use, a baseball hits terminal velocity after about 4.35 second of free fall, during which time it travels 302 feet. I've seen values of both about 95mph and about 72, and using the 95 value. Even when you account for that, a 7.38sec free fall still would travel 720 feet. I suspect that after you hit terminal velocity for any appreciable amount of time, the timing approximation would have to change.