BP shelf life

[Merlin]

The way we must store our BP obviously lends to the possibility moisture absorption and degrading performance. Does anyone recommend using drierite in storage containers or coating granulated BP with graphite? I have a couple cans of Goex that have been around for years and they still perform so why doesn't homemade BP store as well? Its a lot of work to go to only to have it ruin before it can be used.

I am using the alcohol/red gum method for granulation and after a few weeks am seeing a marked reduction in performance. I have also read once BP does absorb moisture you may as well dispose of it. Any thoughts or advice on this subject?

[pyrokid]

You've only had one instance of this happening, so it could very well be some kind of aberration. With that said, you might give dextrin a try. I use lift that is two years old on occasion and I get great results.

[dagabu]

I have some ESTES motors from the 1960's that work as well as they did when I was a kid, in England, there were several casks of BP found in a dungeon from the 1300's that still have the same power as Roger Bacon's Opus Majus and Opus Tertium depict. The basic ingredients, unless whetted to dissolve the saltpeter, do not dissipate or spoil.

[Arthur]

Certainly the British Navy used to dry their powder if it became damp

[Merlin]

All of my BP Fg FFg FFA --all of it has lost it's strength for whatever reason. I just launched the same dummy shell using some benzolift I prepared with the same BP and the Benzo was in the acceptable range. There is something about either the red gum alcohol prep or the humidity that has caused my BP to be useless. I dont really know how the British Navy or ours prepared their BP or kept it dry! I am on this forum for some HELP. So far, I hear use dextrin, and put silica gel packs in with each container of BP and to use graphite for a coating. Goex lasts for years without any humidity control. That leaves dextrin/water as a solvent or graphite as a coating.

I assure you the old saying "keep your powder dry" applied to the brits as well as everyone else.

[rogeryermaw]

it has been noted here that black powder may actually be more sensitive to ignition at 5-7% moisture than completely dry.

 

now if it was stored in a way that it was open to atmospheric moisture, i would hazard to guess that it may be possible that humidity could cycle enough to dissolve and then leach a small amount of the potassium nitrate out of the b.p.? but you stated that it is kept in a controlled climate. google search yields little...

Edited September 2, 2014 by rogeryermaw

[dagabu]

BP prepared any way other than good old KNO3, Sulfur and Charcoal ONLY is open to decay depending on the binder and other additives, I am speaking of good ole 75:15:10.

 

Yes, it is proposed by some good old boys on a cowboy shooting site (they don't shoot cowboys though) with PhD's that the water acts as a heat carrier between grains, propagating the flame front at greater speeds.

[rogeryermaw]

i can't comment on binders or their effect on long term storage as i don't use any binding chemical. i mill, mix with just enough water to get it to stick together and break into grains by hand. after it is completely dry, i sieve into 2-3f, 3-4f and 5f or finer. store sealed in tupperware containers and that's it. never had an issue. (knocking wood)

 

i have to argue with you here dag. i've seen enough audie murphy and james arness to say that those crazy cowboys shoot the crap out of each other!

 

edit: merlin, you know that goex rolls their b.p. grains in graphite, right?

Edited September 2, 2014 by rogeryermaw

[dagabu]

LOL!

[Merlin]

Thanks. What a mystery. I just made a pound using dextrin/ water. About a week from now I will try it! I have ordered graphite and desiccant. I just dont understand. I am talking a couple months of storage not years. At least my rubber stars still work. I dont just give up easily- but obviously I do have a problem. I will try another run without any binder. By the way I dont do shows I am just doing this as a hobby since retirement but the shows I have seen by pros have been spectacular. I just love a good shell burst in the night sky.

Is Harry Gilliam on the up and up?

[VaterAraignee]

@ Merlin

 

Was the humidity at the same level during the reduced performance as the one you are compairing it to?

The air temperature?

The barometric pressure?

Wind speed and direction?

Clean mortar?

This is by no means an exaustive list of what can effect burn characteristics AND your dummy shells ballistics. Then you have the list of things that only effect one or the other.

 

The qoute is "Put your trust in God, my boys, but mind to keep your powder dry.'' I.E. God helps those who help themselves.

A better quote would be.

You're better off drying your powder before you need it than counting on God to make it burn wet when you do.

Edited September 2, 2014 by VaterAraignee

[rogeryermaw]

Thanks. What a mystery. I just made a pound using dextrin/ water. About a week from now I will try it! I have ordered graphite and desiccant. I just dont understand. I am talking a couple months of storage not years. At least my rubber stars still work. I dont just give up easily- but obviously I do have a problem. I will try another run without any binder. By the way I dont do shows I am just doing this as a hobby since retirement but the shows I have seen by pros have been spectacular. I just love a good shell burst in the night sky.

Is Harry Gilliam on the up and up?

good attitude. don't give up. my first pyrotechnic attempts were a total bust. i still suck at it but it's in my blood for good. all the mechanical interest...all the technical skills...the years studying chemistry...have all come together in a love for pyro i sort of knew existed when i set my bedroom on fire at age 4.

 

i don't know harry but his tutorials are fairly sound. he has been described as the consummate businessman why loves pyro. i have bought from his site and been pleased.

 

and i must disagree that black powder that has been wet is useless. KNO3, S and C don't evaporate. though a good soaking may ruin its desirable properties, after it is dry, toss it back in the mill for a couple of hours and bob's yer uncle!

[wildcherryxoxo]

So, why do BP based stars burn like shit if they are still wet?

[rogeryermaw]

water doesn't burn and carries away the necessary heat to initiate the reaction properly.

[Merlin]

OK. All i can say it my original alcohol/red gum performed beyond all expectations. The very same did not a few weeks later. It is either the red gum/alcohol formula or the humidity.

I have prepared the dextrin/water BP and will test shortly. As for my stars, yes, they burn well, but they do not explode as you would expect lift or burst. Stars are a different animal.

Skylighter advised to dry BP in 225 degree oven. Dont know bout that. Have disposed of all old BP. Maybe it can be reconstituted I dont know. Driying BP in oven raises some concern for me.

I must needs to build a drying box. At any rate, I will never give up!!!

My benzolift did work quite well prepared the same time as my BP lift. But you are not a real pyro if you dont get good results with good ole BP!!!! I suspect the alcohol /red gum formulation.

Grandmaster is usually right!

Will continue and report back. This is a great hobby.

Edited September 4, 2014 by Merlin

[dagabu]

OK. All i can say it my original alcohol/red gum performed beyond all expectations. The very same did not a few weeks later. It is either the red gum/alcohol formula or the humidity.

I have prepared the dextrin/water BP and will test shortly. As for my stars, yes, they burn well, but they do not explode as you would expect lift or burst. Stars are a different animal.

Skylighter advised to dry BP in 225 degree oven. Dont know bout that. Have disposed of all old BP. Maybe it can be reconstituted I dont know. Driying BP in oven raises some concern for me.

I must needs to build a drying box. At any rate, I will never give up!!!

My benzolift did work quite well prepared the same time as my BP lift. I suspect the alcohol /red gum formulation.

Grandmaster is usually right!

Will continue and report back. This is a great hobby.

 

Keep working on it, you will find the cause soon enough.

[Arthur]

At Royal Gunpowder Mills Waltham Abbey they made most of the UK's BP (and later other stuff) but they never junked anything, They pressed the grains without binder. If powder started to break up ans dust it was remilled for a short time and re pressed. If it was unsalvageable they would soak in boiling water to leach out the nitrate fro recrystalisation and reuse, and perhaps resublime the sulphur.

 

I suspect that every country with a navy using black powder found their navies redrying powder quite often.

[Bobosan]

Dry it in the sun and re-mill if needed.

[wildcherryxoxo]

Drying in the sun has always caused either driven in stars, or crystallized potassium nitrate. It's best to dry everything out of direct sunlight.

[Bobosan]

Drying in the sun has always caused either driven in stars, or crystallized potassium nitrate. It's best to dry everything out of direct sunlight.

 

Always? Not that I've experienced.

[rogeryermaw]

drying in the sun works ok for me but keep an eye on the temperature. as the powder is black, it will absorb a tremendous amount of heat. as for stars, yes. moisture can be trapped easily in certain comps but if you don't use a binder in your b.p., it is less of an issue. for drying your b.p., more important (in my experience) is to keep air moving around it(low volume to avoid the powder blowing all over)

[MrB]

Drying in the sun has always caused either driven in stars, or crystallized potassium nitrate. It's best to dry everything out of direct sunlight.

Weird since the Chinese have a habit of drying everything from tiny mm large stars, to walnut sized charcoal based stuff, on huge tables in the sun. If they expect rain, they pull a cover over, and thats about it.

But what do they know, fookin amateurs. You should start a business and travel around between the factories, and explain to them why what they do is wrong, and how huge the issue is.

B!

[wildcherryxoxo]

it's common knowledge that drying in direct sun causes problems. Now yall are just trying to pick a fight with me

[MrB]

Ah, yes. Were all trying to pick a fight with you. This is from a Japanese factory:

https://www.youtube.com/watch?v=_dINxkFcmc0

We all know Japanese fireworks suck, must be due to the driven in stars.

Zambelli Fireworks, works from within the states, so clearly, they to much be amateurs, and the reason all things they produce sucks, is clearly from the drying process as well:

https://www.youtube.com/watch?v=G5R-F1RmL5Y

(sorry about the texting, i couldn't find one without it in my haste)

 

Not to mention, as i said before, virtually every Chinese factory under the sun, dries their stars outdoors, without covering em up. The simple fact is that your assumption that drying stars in the sun equals

driven in moisture inside the stars is false. Live with it. Different star compositions have different characteristics. Weather or not they might become "driven in" is one of them.

B!

[dagabu]

Even the venerable Mike Swisher quotes Landcaster just this week saying to lay the fresh pulverone out in the sun to skin over and re-screen. I am not aware of BP being driven in, it could happen I suppose but I for one dry my BP in the shade where possible but at PGI, I was forced to dry it in the sun, the BP was indiscernible in endburners.