Powder Storage Container

[NotSoFast]

I've searched the web and three forums for answers to my question with little to show for my time.

I'm looking for plans, specs., etc, to build a gunpowder storage box. I know I need one if I go over 20 lbs.

http://www.alliantpowder.com/safety/storage.htm

I know safes and non-vented storage is out as that leads to explosions which would just about ruin my day/week/month/... And I really don't want some funky smelling gym locker either. The milsurp motif just doesn't get it for me.

So has anybody built a 1" thick storage cabinet or box for storing their powder? I'm planning on making a big purchase and will need room for about four 8 lb. cans of powder (32 lbs.).

[Mikeb]

I like my plastic ice chest. Insulates from heat in case of fire and is not tight to cause a kaboom. But I would suggest you check your local regs for amounts and requirements. I believe wooden chests are considered good.
Mike

[NotSoFast]

I like my plastic ice chest. Insulates from heat in case of fire and is not tight to cause a kaboom. But I would suggest you check your local regs for amounts and requirements. I believe wooden chests are considered good.
Mike

Thanks for your idea. That may be a temp solution for me for now. But I do know that wooden chests are not only good, they are highly recommended. And so I was looking for plans to build one. So far I've come up with zilch for solid info.

If I have to I'll get an 8 lb. cannister of my favorite powder, BL(C)-2, and measure it to get an idea of how much space I need , then build my own from scratch. While I'm not a journeyman carpenter, I think I can throw something together that works.

Here's something to think about, and why they recommend wood. In a fire, the plastic cooler can actually melt and thus lose any insulating properties. Wood, on the other hand, while it insulates less, it lasts and protects longer. And if it does go, chances are the whole house is a goner anyway.

They found this out in controlled tests. Wooden chests actually protected what was inside much longer than even solid metal cabinets the same size. Papers were placed in each and then surrounded with a controlled heat of that of a home fire. When everything cooled, while the papers in the metal cabinet were destroyed, the papers in the wooden cabinet fared much better and had little damage. Just something to think about.

Funny what you run across at times and wonder "Now what good is this info?", then years later something like this comes up and I go "Oh, yeah! I remember."

[50BMGBOB]

The chest I built was out of 1x boards so the wood is 3/4". The inside is lined, lid, bottom and walls, with sheetrock for added insulation. Don't forget, the ideal is not to let pressure build up. I used finish nails (no heads) and just the minimum number. An 8lbs canister is roughly a gallon of milk or bleach. Hodgdon changed the shape of their canisters sense I built mine so don't build it to tight. Mine will hold six 8lbs jugs with a little extra room. I usally order two jugs at a time when I start to get low so that is twice what I usally need. But like a gun safe, to big is better than to small.

[NotSoFast]

The chest I built was out of 1x boards so the wood is 3/4". The inside is lined, lid, bottom and walls, with sheetrock for added insulation. Don't forget, the ideal is not to let pressure build up. I used finish nails (no heads) and just the minimum number. An 8lbs canister is roughly a gallon of milk or bleach. Hodgdon changed the shape of their canisters sense I built mine so don't build it to tight. Mine will hold six 8lbs jugs with a little extra room. I usually order two jugs at a time when I start to get low so that is twice what I usually need. But like a gun safe, to big is better than to small.

Thanks for your help and comments. That's about what I'm looking for.

[50BMGBOB]

I am not familiar with flagstone tiles so I don't know. As for hardware, my lid is the top. The wood rest atop the sides and the sheetrock is cut to fit inside the wooden part of the side. No hinges or latch. It sits right under my reloading bench which is in a Shed with power that I can lock to keep my kids away. I also store my ammo there.

On a side note, they should be as low as possible. The floor or a low shelf is cooler in a fire than it is on a high shelf. All my powder and ammo is low. Dies tooling, empty brass, books, etc can go on the top shelfs.

[rayra]

Not so fast, NotSoFast. You link a good source (Alliant's pages on storage), but you seem to have severely missed the point - flagstone?? You're building a grenade and encasing it in prefragmented shrapnel.

The point of a powder magazine is to secure the goods and control the burn, not prevent it. Any steps you take like thick walls, strong latches, encasing it in STONE are all 180-degrees wrong. You build it EXPECTING it to burn. The magazine protects the powder from incidental and short-term exposure to fire. But if you have an actual structure fire you WANT that powder to burn in a controllable fashion (like a big roadflare), instead of a massive detonation.

Your acct says the East Bay. You should contact your local fire dept or their HazMat dept if it's a large department, and ask them for guidance. This is a major safety issue. One that's already been solved. Don't think your way into a major mistake while trying to reinvent a solution.
Also, there are probably limits you need to be aware of. Here in L.A. County IIRC the limit (for private individuals, not a business) is 24-lbs of smokeless powder and I think 5 of black powder.
East Bay / Oakland is sure to have something at least as stringent.
Step #1 is knowing the law, before you decide what to do about it.

[Builder]

http://www.usexplosivestorage.com/hazardous_material_storage_products.htm

http://www.cabelas.com/spodw-1/0012533.shtml

http://www.luckhardt.com/ecwsa106.html

US Government specs for Black Powder Storage Box.
WAC 296-52-70065 Explosives day box.
(1) A day box for explosives must:
Be fire, weather, and theft resistant
Be used in a manner that safely separates detonators from other explosives
Be constructed of a minimum of number 12 gauge (.1046 inches) steel
Be lined with at least either 1/2-inch plywood or 1/2-inch masonite-type hardboard
Have doors that overlap the sides by a minimum of one inch
Have appropriate ground slope for drainage

(2) Hinges and hasps must be attached by:
Welding
Riveting
OR
Bolting nuts on the inside of the door

(3) One steel padlock, which does not need to be protected by a steel hood, having a minimum of five tumblers and a case hardened shackle of a minimum of 3/8-inch diameter is sufficient for locking purposes.

[NotSoFast]

I think, while you point out a possible hazard, have jumped to a conclusion based on limited knowledge of what I proposed. Yes, I am guilty of not giving enough information. But I did not say that I would make a tight enclosure that would allow an explosion to occur. I was thinking of loosely attaching flagstone tile, smaller than each of the wooden sides, in order to help keep away flames as long as possible. And that includes the side used as the entrance to the box. How I would do that I have not completely figured out, but it is a consideration. Whatever it is, it will definitely NOT be airtight or capable of allowing detonation.

I know quite a bit about ordnance and explosives from my time spent in teh Navy working with ordnance devices. I have a healthy respect for them and what they can do, as well as how to operate in a safe manner, handle and store them.

The purpose of the box is not that it will burn. Yes, it should be loose so that the powder can't explode if fire does reach it. But the real purpose of building it out of wood is that wood is an insulator that is safer than other insulating materials in a fire. Wood will transfer heat much slower than a metal housing. And plastic coolers will melt, leaving almost no protection whatsoever for the powder. In my suggestion, the rock also transfers heat slower than many other materials and is fireproof in itself to boot.

I had already planned to follow your advice about contacting fire officials about this though. Thanks for pointing out my failure to give details.

[NotSoFast]

After talking to my coworker, a fire inspector for over 10 years, here is what was recommended:

Build a box of 1" wood. Cover it with 5/8" sheetrock. Make a cover of, from inside out, 3/4" wood, 1/4" plywood, topped by 5/8" sheetrock. The lid/door should seal but not be so snug that it won't open easily. If the gunpowder does ignite, it will pop the lid off, along with every window in the building, and allow the remaining powder to burn rather than explode.

The wood/sheetrock combination gives a 1 hour rating. That means that it will take an hour for the heat to cause the gunpowder to reach spontaneous combustion temperature. The wood is chosen because it is an insulator, not for any other reason. So, unless the whole building goes, or that room goes completely, the contents of the powder box should be safe for an hour.

And, for looks and added safety there is a paint that will, when exposed to flames, foam up and give an even longer safety margin. It's expensive though, costing about $50 a gallon. I haven't researched it yet though so I'm not exactly sure of that price or where to get it. He also recommended using wood trim on the corners of the sheetrock for looks and to keep the sheetrock from chipping, etc. Tape and metsl sheetrock corners are not recommended in this application.

I am editing my other posts about the flagstone, although it would work, just not as effective as sheetrock.