What's Wrong with Corrosive Ammunition?
By R.K. Campbell

When it comes to ammunition, too often myths and misinformation are an impediment to advancement in training. Training properly demands lots of ammunition. It should be stressed that the two things you do not wish to run out of in a fight are time and ammunition. The same is true in training. Invest time and ammunition in training and train properly. Affordable ammunition is important. During the lifetime of the firearm a serious shooter will spend more on ammunition than on the initial purchase of the firearm. Everyone wants clean burning, accurate ammunition. One of the best resources for good quality affordable ammunition is military surplus sales. All of us are painfully aware of the high and increasing costs of components and ammunition. Several of the major makers are now offering steel cased ammunition, a sure sign of a problem in obtaining raw material. There are times when quality surplus ammunition is available for about the same price as putting together personal handloads, but without the time and labor. Surplus ammunition was often produced at a time when prices were lower and this cost savings is passed on to the end user. A handloader may enjoy loading but most will enjoy shooting more. While handloading is rewarding on many levels, the time spent in loading the prodigious amounts of rifle ammunition used in training and the occasional competition is a daunting proposition. For the occasional shooter or hunter high ammunition cost is more of an inconvenience than a hardship. Firing a modest amount of ammunition to sight the rifle is all that they look for. More is better for marksmanship. Action shooting is a different neighborhood than casual shooting. Often the ammunition cost is the most significant factor in a match.

When looking at surplus ammunition, do not attempt to understand global markets and wonder why a country has shed themselves of this ammunition. Enjoy the bargain. The U.S. Military is using all of the 5.56mm, .308 and 9mm they are able to obtain, and so are our allies. Just the same there is ammo available for those who are willing to search and be diligent. Many shooters shy away from corrosive primed ammunition, and a significant quantity of the available loads are corrosive primed. These shooters have heard of corrosive primers turning the bore red (or rather the residue from such primers), of rusted bores and flash hiders, of rusted bolts and generally corroded firearms. And all overnight! Hand loaders have cursed crimped-in military primers, which make for added difficulty in reloading corrosive primed brass. You also must clean the brass more thoroughly to remove all corrosive residue before reloading. Then, there’s the problem of Berdan primed cases, a whole different ball of wax. Sure, you have heard it all and there are still plenty of shooters using surplus brass and ammunition. Not only do they use this ammunition for training for the most part but many trust this ammunition for personal defense and use it in competition. For the better part of the twentieth century corrosive ammunition was in use by all of the world's armed services and practically every round of small arms ammunition fired in World War One and the majority fired in World War Two were corrosive primed rounds. The first move to non corrosive priming came with the introduction of the .30 M1 carbine. The military’s first low maintenance rifle, the carbine required non-corrosive ammunition because maintaining the carbine did not include scrubbing the gas cylinder as was required by the M1 Garand. This move to lower maintenance eventually resulted in the gas impingement system of the AR-15 rifle, although the M14 rifle demanded more care for reliability. While the United States began the move from corrosive ammunition during the 1950s, many nations continued to produce corrosive primed ammunitions until at least the 1960s. Match grade and sniper grade rounds were corrosive primed, so obviously this ammunition was not second class compared to modern loads, it was simply primed differently.

What is corrosive priming? Corrosive primers contain potassium chloride and sodium chloride. These elements are very stable and these primers are completely stable at both very high and very low temperatures. Soldiers operating in the Aleutians or the sub Saharan desert are confident these primers will always fire and that they will be consistent and not demonstrate pressure spikes. While modern technology no longer demands these compounds, in their day they were useful. Corrosive primers were a slight inconvenience compared to the previous black powder military cartridges. These compositions are actually not corrosive on their own but rather corrosive in that they attract moisture. If they were corrosive themselves they would rust out of the primer during storage. The bolt, barrel, bore, action, gas cylinder and any muzzle brake or flash suppressor are especially susceptible to corrosion induced by these compositions. In short, corrosive primers have no negative affect on reliability but rather enhance reliability. The conditions under which the loads were stored is more important than the priming. Surplus loadings are produced around the world, and while accuracy and quality control differs, European surplus is often very good. Canadian 9mm Luger ammunition was once highly prized because it would run a German Luger with good function and accuracy, while domestic loads would not. Greek .30-06 ammunition was highly prized for reliability and accuracy. Yugoslavian 8mm is a good resource to get a good handle on the true accuracy potential of an original Model 98 Mauser. This military spire point bullet loaded ammunition is more accurate than commercial loadings and considerably stronger as well. Thousands of rounds of Com Bloc 7.62 x 39mm, a smaller quantity of 7.62 x 54mm, and even a small lot of Russian 7.62 x 25mm with the 1943 headstamp have been digested on the local range without a single burp. This stuff was old but hot and accurate, which proves sometimes the Russians got it right.

Just how accurate is surplus ammunition? Military ammunition is loaded with reliability first. That is why the corrosive primers and crimped in primers - and sometimes heavy bullet crimps as well - were used. Mass production with ammunition that must always stay within allowable pressure is also important. As a rule of thumb good quality surplus will be as accurate as commercial generic ball loads and often more accurate than foreign produced economy loads, and then everything in between is possible. The results will be consummate with the firing platform. A recent test with a Bushmaster carbine exhibited groups of two to three inches at 100 yards with just about anything. Inexplicably one of the three Bushmasters on hand is noticeably more accurate than the others, but the edge isn’t there with average ball ammunition. It is best demonstrated with Black Hills A Max, which usually groups three shots into a little over an inch to one half inch with this standard carbine. Most surplus is as accurate as most generic ball as a rule of thumb and more accurate than the dirty foreign commercial stuff. It will not be as accurate as the Black Hills 60 grain JSP or the Black Hills 77 grain Open Tip but then what is? Surplus loads are accurate enough for practice and all but bench rest competition.

We should make the point that all surplus is not corrosive, but the majority are. You should regard all ex military ammunition as corrosive primed and follow the proper cleaning procedure unless you definitely know otherwise. There is no lexicon for foreign loads. Now we come to the dirty part of the story. Cleaning the firearms is a necessary chore that some feel they may neglect on a whim with modern ammunition. This type of shooter will need to avoid corrosive primed loads. In fact, he may need to avoid shooting much at all because every firearm needs to be cleaned often to prevent eccentric wear from powder, lead and jacket material build up. To clean a firearm that has been exposed to corrosive priming you follow a program similar to that used with black powder shooters. The firearm must be field stripped but not completely disassembled. The old “Run it under the hot water” trick certainly is an option, but one that should be used sparingly. Rather, the program begins with carefully field stripping the piece and then using powerful ammonia to clean the bolt, bore, trigger mechanism and in those firearms that use them, the flash hider and gas cylinder. You must be completely thorough in using this ammonia to clean the firearm. The spray bottle most often used is simple household glass cleaner. It always works just great. However, you should sometimes use hot water after the preliminary cleaning with ammonia. Running the part under the faucet is all that is necessary. It is not necessary to use boiling water; at least many firearms are a testimony to this program.

When all is said and done surplus ammunition is a good resource for those who wish to shoot plenty of ammunition at a fair price. Thousands of shooters have used surplus ammunition for many years and have enjoyed good shooting and excellent service. That is all we may ask of anything man made.

This article first appeared in Small Arms Review SAW (July 2012)
and was posted online on May 4, 2012


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