Potential Field Box Source

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Well-Known Member
Jan 19, 2009
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I just purchased two 30mm ammunition containers from a company that mainly deals in survival equipment. These would make fine cases for engines, at least that's my intended use. I've been buying MREs from this company for years to use in taking our church youth group backpacking and have never had a problem with their service.

Am I on the right forum? Oh, I must be - they won't let me read my shooting forums at a work! :D

For LPR motors, an organizer that I really like is the one shown in post #10 of this thread https://www.rocketryforum.com/showthread.php?t=569 I picked up a couple of these a couple years ago, and they are perfect. 18mm and D BP motors will fit standing on end. I thought they were out of production, and Stanley doesn't show them on their website that I can see, but I saw a very similar product for sale in Home Depot just the other day.
The problem with the "tall" ammo cans is that you'll constantly be digging into it to find what you need.

I found one of these - a flat 20mm ammo can. All my BP motors are in it. (I also keep plugs and igniters in Altoids boxes inside it.)

Being flat rather than tall, you can easily see what you have and get to it without having to dig. You can lay your motors on their sides so you can easily see the labels, and they can also stand on end if you're using some kind of separators like cardboard or plastic sheets.


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Are these ammo boxes constructed of wood or steel? Sorry - I don't know much about that type of container (no mil. background).

Mark \\.
It's steel, with a VERY TIGHT locking latch on the side and a rubber seal under the lid, making them pretty much air tight. I've used one like it to make a geocache, and I use one as a toolbox in one of my cars as well.
I used to use an ammo can long long ago. Here is one of the larger issues I had with it. It got HOT in the sun. For BP engines, getting them too hot can cause a significant higher cato rate. Even worse, engines that have gotten “too hot” will retain that damage so they are just as likely to fail later under normal temperatures.

So, I switched to using simpler things like cardboard boxes, which do not get as hot in sunlight. Same goes for car trunks, or cars, just do not leave engines in cars/vehicles so they can get hot in the summer.

On the flip side, when it is really cold at a launch, do keep them in cars, where it tends to be warmer than outside. Because BP engines also tend to cato more often when they are really cold. So, when you are ready to fly, save loading he engine until last, then get it out, install, put in an ignitor, and fly soon afterwards.

I think the best use of ammo cans would be for those who do not get to store their engines inside an air-conditioned house. If you have to store engine in a garage (a garage that never gets hot, but does get damp), or a damp basement, ammo cans would be a great idea. I myself always keep my engines stored inside where it is air conditioned. I have some old engines (from 1970’s and 80’s) that I know have been stored well, never overheated in the sun, never allowed to get damp, that I expect would work reliably. Then I have others that I do not know their storage history, that I would never put into a good model because of the cato risk.

OK, here is one other good use for n ammo can, even inside of an air conditioned house. For storing composite engines indoors. Humidity can get absorbed into the propellant. The worse cases I have seen this have been some reload packs that I had opened, bun not flown for 2-3 years. Over time, the humidity caused the propellant grains to swell. To the extent that a “C” slot” in a reload grain was almost completely closed shut except for the innermost part of the slot, the rest of the slot walls touched each other.

- George Gassaway
I follow those same parameters, George:
  • I store them in the ammo can inside the house for temperature control
  • At the range, I keep them in the ammo can but I take the lid off or leave it loose so they can get to ambient temperature
  • I keep the can out of direct sunlight, like under the table or my folding chair