Hunters and shooters are hoarders of many things, not the least of which is ammunition, but how long can we expect it to last on the shelf. As general consensus has it, the smokeless powder and primers in modern ammunition are chemically stable for around 25 years after it is loaded—as long as the ammo is stored in a cool, dry environment. But ammunition has been known to last much longer. I have read that some of the .50 BMG used by American mechanized units in Operation Desert Storm was from World War II stock. If this is true, the ammunition could have been 50 years old.
I frequented gun shows in my area back before they became flea markets, and one guy who always had a table specialized in vintage ammunition for collectors. Most of it was quite expensive, but if a box showed wear or damage or had cartridges missing, prices were often affordable. I used to buy an occasional box, some of it dating back to the 1890s. Just for the fun of it I would shoot a few rounds from a broken box, and seldom did I experience a dud. There was the occasional hang-fire, probably caused by an age-weakened primer, but by and large the ammo shot quite well.
Sometime back I bought a Savage 99 in .22 High-Power which was introduced in that rife around 1912. Te ammo I had on hand was purchased from the gun show guy, and even though it was loaded during 1920s, it shot just fine in my rife. In fact, it was more accurate than my hand-load with the Hornady 70-grain bullet. Am I advocating that everyone rush out and shoot ammunition made a century ago? Heavens, no. I did so under controlled conditions and confess to some of my past sins merely to illustrate the life and reliability of good ammunition. Prior to the introduction by Remington of the non-corrosive primer, the primers loaded in center-fire ammunition contained fulminate of mercury, so immediately after shooting my Savage, I pushed water-dampened cotton patches through its bore to remove the residue. I then coated the bore with oil for storage.
Before leaving the subject of fulminate of mercury, I should mention that while the use of primers containing it in commercial ammunition ended during the late 1920s, they continued to be loaded in military ammunition for many years thereafter. Several of the guys who are members of my gun club shoot vintage military rifles, and they use military ammo loaded in various countries as far back as the 1940s.
One even recently shot 1920s ammo in his Lee-Enfeld, and you should see the stuf they shoot in their AKs. Tey also clean rife bores with water prior to applying a rust preventative.
But there is more to the bad side of corrosive primers than their ability to cause rife barrels to rust. During fring, the mercury amalgamates with the brass of the case, and this chemical attack not only initiates a gradual weakening of the case, it eventually makes it as brittle as a fresh potato chip.
The attack begins immediately upon fring and cannot be stopped by washing in water or any type of solvent. Water works as an efective solvent in a rife barrel because it is made of steel and not brass. Once a case containing a corrosive primer is fred it should be discarded and not reloaded. I suppose it would be safe to reload for a while, but since no one seems to know exactly how long it takes for the case to become too weak to contain the pressures, tossing it is the wise thing to do.
During the early 1980s, I started shooting in handgun metallic silhouette matches, and when Tompson/ Center introduced the 7mm TCU in its 10-inch Contender, I switched to it for Production class competition. Te load I settled on consisted of the Remington 7-1/2 primer and 27.0 grains of H335 behind the Sierra 160-grain boattail bullet. I formed cases by necking up .223 Rem. brass, and since I shot thousands of rounds each year, I used whatever I could come up with, including once-fred military surplus. I was aware of the use of corrosive primers in military ammunition but had assumed the practice had been discontinued prior to the adoption of the .223 by the U.S. Army in 1957.
I continued to load and shoot those cases for several years, and then, when
switching to a more lively game called IPSC, I hung up my single-shooter in 7mm TCU. A while back I dusted of the gun with plans to punch a bit of paper with it. I also discovered some ammo I had loaded for it during the good old days of shooting steel. As I attempted to pull a round from its 50-round plastic storage box, the end of the cartridge containing the bullet broke of at the shoulder. Same thing happened on the next round. And the next.
The case of each cartridge had become so weak and brittle it literally broke in two when stressed by its own weight. Tat was surprise enough, but the big one came when I noted every case was head-stamped “LC 84,” which meant the cartridges were loaded at the U.S. Army’s Lake City Arsenal in 1984. I have no idea what would have happened had I fred one
of those cartridges in my Contender, but my guess is it would not have been at all pleasant. I will continue shooting old ammunition as long as it looks good and appears to have been stored under favorable conditions, but you can bet good money I won’t be reloading the cases.
And what are favorable storage conditions for ammunition? Cool and dry for starters, which means in the trunk of your car during summer and down in a leaky basement at any time are out of the question. Excessive heat is bad, but I don’t believe really cold temperatures hurt anything as long as the ammo is totally protected from entry of moisture. Some folks shrink-wrap ammo in plastic, and while I am sure it is efective, handling can puncture the film.
When all is said and done, I believe Uncle Sam’s .30 and .50 caliber ammo cans will always be hard to beat as long as their rubber gaskets have not deteriorated. Good ones usually run around $10. A friend of mine who continues to collect .223 ammo like a packrat recently paid just over $20 each for cans made for 20mm ammunition. Each one holds more ammo than he can lift.