vacuumed packed ammo ?

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I have a food saver vacuum packer and was just wondering what are the pros and cons of vacuum packing some of my ammo. Will the vacuum cause the gun powder to expand and burn quicker? Will it cause problems with the primers?
 
I was curious of the pros/cons too. I know the "SPAM" cans often found with Russian ammo are vacuum packed. I assume there is a good reason for it aside from just keeping the ammo dry.
 
If I vacuum pack them I can "hide some " for use later without worrying about the ammo can rusting.

You don't need a vacuum for that, just a watertight seal. In fact, a vacuum could make it worse, if you have a bag with a vacuum inside it that gets a hole in it, even a pinhole, it's going to suck into the bag whatever's outside that hole. If it's water, now you have a bag full of water.

Also, I read an account once where someone vacuum sealed ammo and the pressure of the bag sucking up against the ammo actually pushed some of the bullets in a little, screwing up the setback, which could be very unsafe.

I think on the whole, a dessicant pack in a heat-sealed bag without a vacuum would probably be better.
 
My original response to the above thread:

Good theory, but possibly bad results. I was going to do the same thing until I remembered my "Mr. Wizard's World" re-runs.
Keep this in mind: when you create a vacuum (ie: inside the container holding the ammunition), any air pressure inside an enclosed container (ie: the bullet) now has a higher amount of air pressure than its surrounding area. In theory this could cause problem with the ammo, such as the air inside the bullets trying to go to an area of lower pressure, causing possible dislodging of the bullet or primers. Kinda like in science class where you put a tied, but barely inflated balloon or marshmallow in a vacuum pump and turn it on.. the thing puffs up.

Now, I have not tried this experiment with ammo, although I have vacuum sealed containers within other containers before with the above mentioned condition becoming the case (the internal container popped open). If it was a good idea, the military would be doing it with their battle packs. I would go with a non-vacuum sealed heavy plastic container with a moisture absorber in it. You could buy the absorbers online, or ask your local computer geeks to save them for you when they get new equipment in. If you have a food dehydrator, put them in it on a LOW setting for a few hours and they will be good as new.
If you feel you *must* try to vacuum seal the ammo, I would go with a VERY low vacuum to remove most of the air, but not creating a negative pressure environment.
 
I've never vacume packed ammo myself, but I doubt it's going to cause any real problems. The most negative pressure you're going to create between the bag and the air trapped inside the bullet is 15psi. The bullet should be able to withstand 15psi without any damage at all. Think of how much force it takes to pop a primer when reloading. The primer's area is less than 0.03 square inches, so that's less than half a pound of force pushing out on that primer. ____ The idea of vacume sealing it to get as much latent moisture out before you seal it in and not have your storage method take up any more volume than necessary. You're best bet would be a low pressure vacume (pull the pressure to -5psi under atmosphere) seal done on a cool Febuary day when the fireplace is running full blast so the air is as dry as a bone. ____ If you're going to do that, also seal your bullets and primers, lay your sealed packs in an ammo can and seal it up. You've got very long term storage of ammo, even if it's sitting at the bottom of the water.
 
Johnny,

Do you know what is the negative pressure capability of your vacume sealer? I have fired ammo that has been shipped in the cargo area of a plane, which exposes it to about -10psi verse any air trapped inside the cartriage during its manufacture and experienced no problems. Now that's only 4-6 hours exposure to low pressure. Run an experiment - Take a 20rd box of ammo and place 10 rounds in a vacume sealed bag and then place 10 rounds in non-vacume sealled bag on the same day.

In August, take the 2 bags out to the range with a chrony. Measure the velocity of both ammo alternating between round sources. Compare: Cold Bore point of impact, Hot Bore point of impact, group size and average velocity for the two ammos. I expect that you'll find them nearly identical.
 
I've checked the vacuum sealer and can't find the manuel for it so I don't know what it draws. I was hoping that some one out there had already tried this, or at least something close.
 
I've fired previously vacuum sealed ammo, right out of the bag and noticed no difference in performance.

A tip for you, double bag it. Seal the ammo in a feezer bag then in a vacuum bag, otherwise, the first or second time you handle the stuff(pointed FMJ rifle ammo) it will lose its vacuum.
 
I've fired previously vacuum sealed ammo, right out of the bag and noticed no difference in performance.

A tip for you, double bag it. Seal the ammo in a feezer bag then in a vacuum bag, otherwise, the first or second time you handle the stuff(pointed FMJ rifle ammo) it will lose its vacuum.

I was thinking of vacuuming sealing it twice,,,just in case
 
I read that vacuum sealing ammo is NOT a good thing to do, as it may cause the bullets to be unseated , as the air inside the case trys to escape.

Just through a desicant pac inside of the 30cal ammo can that has good rubber seal and you should be good.
 
this is one of the better reasons that I've heard. I not sure that it will unseat the bullet but it is something to look for when I try it. THANKS
 
A sugestion - use the foodsaver bag, for the ammo storage, but do NOT vacuum the air out...just compress it as much as you can, and seal it. That way, it is sealed, keeps the moisture out, and you avoid the danger of the vacuum unseating the bullets.

I'm thinking that I am going to do up a package each of a couple of my extra/duplicate spare pistols , like VZ52 and Makarov...vacuum seal up the pistol, and then in the next section, place some ammo , NOT vacuumed, and seal it, and then in the final section, vacuum seal up the leather holster.
 
I read that vacuum sealing ammo is NOT a good thing to do, as it may cause the bullets to be unseated , as the air inside the case trys to escape.

I find this highly unlikely:

Atmospheric pressure is approximately 15PSI, if the bag is completely vacume sealed (true zero atmosphere) the air inside the round would push on the inside of the bullet with 15 pounds per square inch.

Let's see: 50 caliber bullet = 0.25^2 * Pi (3.14159) * 15 = 2.9 pounds

If 2.9 pounds of force is sufficient to dislodge or even unseat the bullet, it would be dislodged by recoil in the magazine. (A .30 Caliber comes to a hair over 1 lbs)

Even with the air within the case being compressed by the act of seating the bullet to 2 atmosphere (reducing the air volume within the case by 1/2) you're still talking about 6lbs of force on the .50 caliber and 2lbs of force on a .30 caliber. Far from sufficient to dislodge a seated bullet.
 
A sugestion - use the foodsaver bag, for the ammo storage, but do NOT vacuum the air out...just compress it as much as you can, and seal it. That way, it is sealed, keeps the moisture out, and you avoid the danger of the vacuum unseating the bullets.

I'm thinking that I am going to do up a package each of a couple of my extra/duplicate spare pistols , like VZ52 and Makarov...vacuum seal up the pistol, and then in the next section, place some ammo , NOT vacuumed, and seal it, and then in the final section, vacuum seal up the leather holster.

You just reminded me that I vacuumed a Makarov and Ammo some years ago,,I should go dig them up and see how they turned out

I mean dug them out?????
 
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The bags loosen up. A few years back I tried it with a few boxes of 9mm. You can pull a tight vacuum in the bag and seal it. A few weeks later as air escapes from the shell the bag will puff up again and feel loose. I did not notice any problems with any of the shells, but I have no idea if they would have been more prone infiltrates after having the air sucked out of the sealed case. I don't bother with it any more. If I want to protect them I just seal the bag with a desiccant pack inside. I don't see any other reason to try to pull the air out.
 
Try to vacuum pack a few rounds and leave them for a week or two. Then unwrap them and check the OAL and look at the primers to see if anything has changed. Now pull the bullets from the brass and inspect the powder to see if it has changed in appearance. I would even suggest using reloads of known powder type and volume/weight, and then checking after vacuum packing again to see if it has gained/lost any volume. And also verify weight again to be sure none is stuck in the case. I would believe if nothing has changed that it would be time to test fire and check for function/reliability.Although I have no experience, I would try it this way if I were to do it. I would trust in evidence over hear-say unless you find somebody with first-hand experience. Good luck and be safe.
Kenny
 
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