Do you have ammunition for your firearms that you don't plan on using soon, and want to know the right way to store it? You'll definitely want to know what your options are and how each one is different. Proper storage is going to prevent the casings from corroding and make sure that the ammunition is ready to go when you need it.
You always have the option to keep the ammunition in the original box. Since the box is not sealed, there is the greatest risk of the casings becoming corroded due to moisture. This is true of all original boxes that are made out of cardboard, even if the casings are placed in foam to hold them in place. Some boxes have a plastic tray that does a better job than foam, but it is still not ideal.
Do you have a vacuum sealer that you use to preserve food in your kitchen? This can actually be used to store ammunition in a relatively cheap way. The vacuum sealer is going to remove any air from the package, which will prevent the casings from corroding. It is also a good idea to put a silica packet in the package to absorb any moisture that is still in there.
Vacuum sealing is ideal if you do not have a lot of ammunition and don't want to spend money on a case for it. The seal will also let you know if anybody has opened the package since it will be quite obvious if the seal is broken and the air gets inside it.
Plastic Ammunition Can
One of the cheapest ways to store ammunition will be with a plastic ammunition can. Even cheap plastic ammunition cans do have an O-ring around the lid to prevent moisture from getting inside the ammunition can. However, the plastic ammunition cans do have flexibility to the material, meaning that the seal of the O-ring can be broken and let moisture in. That's why this storage solution is not ideal, but can still get the job done if you are on a budget.
Metal Ammunition Can
A military-style metal ammunition can is the best way to store your ammunition. This is the same type of ammunition can that is used around the world, which is because of how good of a job it does at protecting the ammunition. The main advantage of a military-style ammunition can is that the seal around the lid is not going to break if the ammunition can is dropped.
Contact a local gun shop to learn more about storing ammunition, including 9mm ammo.