Letter: Vacuum Sealing Ammo


I have been thinking of vaccum sealing my storage ammo and just use wood crates to store in bulk. You know, I’d do it with a common food sealer system. Has anyone tried this or made suggestions in this area? Any feedback (good or not) would be greatly appreciated! – C.P.

Hugh replies: You can seal your ammo, but you need to be careful about what type of ammo. The powder contains its own fuel and oxidizer (as does the primer), so a storage in a vacuum should not harm the active components. You may still have some tarnishing though, as the powder will outgass under vacuum conditions. However, since the ammo is produced at roughly 1 atmosphere of pressure, you will have approximately 14 psi pushing on the back of the bullet during the storage. If your crimp on the bullet is not tight, it may push the bullet out of the cartridge or change the overall length of the cartridge, possibly creating an unsafe condition when the ammo is used. Use vacuum sealing with caution, and check your ammo at regular intervals. Personally, I do not vacuum seal ammo, but I do use just the sealer portion of the vacuum machines to seal the ammo in plastic with a moisture absorber to keep it dry. I prefer this method, because of the failure mode of vacuum sealing. If you have a breach of the plastic barrier, the vacuum will pull the atmosphere surrounding the bag into the bag. If that atmosphere contains high levels of moisture, you defeat the purpose of the packaging. By using a normal atmosphere level, with a moisture absorber, a small breach does not pose any issues.