Debunking Steel-Case Ammo Myths

by Frank Melloni, Renaissance Firearms Instruction

Oh, I can see the comments now! Yes, I use steel ammunition. Yes, I use it professionally. Yes, I use it personally. Yes, I compete with it … And yes I do well! Steel-cased ammunition has always had a place in my locker. I have used it to develop my skills and still use it today. We use thousands of rounds of this ammo a year, in several different calibers with great results. Allow me to take you through some of the details and concerns of using steel cased ammo and how and where to use it for the best results.

Let’s start with an accurate look at exactly what the role of a cartridge case is. For a cartridge to function properly it needs to do two things: Seal the chamber during firing, and release from the chamber walls quickly after the bullet leaves the barrel. During the firing of a cartridge, the case will swell to the chamber walls, sealing it in the process. This protects the shooter from the burning gasses and back pressure created by the ignited gunpowder. After firing, the case will cool and contract, making extraction easier, or in tight chambers even possible at all. Both of these functions in relative terms so that means several materials will fit the bill. Many ammunition companies and wildcat reloaders realize this and thusly have experimented. Let’s discuss their findings.

Topping the list is brass, the undisputed most widely used metal. Brass is extremely ductile, meaning it can be bent over and over again without snapping. Brass also is very soft and dissipates heat quickly. These features make it perfect for ammunition cases, however at a premium price.

Next down the line is aluminum. As it costs less than brass it certainly is worth examination. Aluminum cools very quickly, faster than brass in many cases. For this reason, it is used in engine blocks and radiators. While cooling quickly, Aluminum suffers from a lack of ductility. Think of a soda can tab, maybe 10 full bends and it snaps. Aluminum ammo users often complain about cracked cases. These cases crack because after their initial sizing and crimping the metal case doesn’t have much life left.

So this leaves steel. It certainly is the least expensive metal. It offers a better lifespan than aluminum. Steel comes in many different grades or hardness ratings. Steel does the job, except it suffers from two issues, corrosion and a reduced rate of heat dispersion. These two factors can lead to issues if not addressed correctly.

The first solution was to simply apply lacquer; this is a cheap and easy way to keep the steel from corroding. The problem with lacquer is that in the past it led to jamming, especially if it melted into chambers. Most steel companies solved this by switching to a polymer coating on their rounds. Polymers are an ingenious solution to the corrosion problem and obviously help with feeding issues. Some brass cases even use a polymer coating to help aid cycling, such as 5.7×28 FN. A myth is that polymer is just another name for lacquer—this is false! There are still a few people from this camp floating around saying that it will melt just the same, also false. Polymers are made to endure the high temperatures barrels and chambers reach, without melting. Remember, most pistol frames are made from polymers!

The other problem is the lack of heat dispersion. Steel doesn’t do as good a job as brass, but remember it only has to be so good. Steel will remain hot longer after firing, but depending on your firearm there is little chance of this being an issue.

The “stuck case” issue that follows certain firearms isn’t an issue of the steel ammo being out of spec. Quick measurements and a cross-check with a reloading manual shows that the ammo meets SAAMI’s specifications. The problem with stuck cases is steel just being steel. Steel just doesn’t do the same job that brass does when it comes to sealing the chamber. While perfectly safe and acceptable, there is some gas seepage. This leads to accelerated carbon fouling. This fouling leads to tighter chambers and eventually stuck cases.

So what do we do?… Clean your gun! You should be doing that anyway! At Renaissance Firearms Instruction we run close to 500 rounds through our guns on any given day. We clean them afterward and enjoy a trouble-free relationship with this ammo. This includes AK47s, AR-15s, Beretta 92fs, M1 Garands, Mosin Nagants, and a plethora of rotating test firearms. Just clean, oil, and enjoy!

One last one before we wrap it up, “steel ammo is going to damage your gun.” This one makes the hair on my neck stand up. When I hear it I not only question the perpetrators’ knowledge of firearms but their general grasp on life. Let me ask this, how can steel be so hard it can damage a gun, and then be formed to gently hold one of the softest metals on earth (lead)?

Steel (again) comes in different grades, just like plastic, brass, and wood! Your chamber, barrel, and extractor are all made from some form of ultra-rigid tool-grade steel, it wouldn’t fire very long if it wasn’t. Steel cases in ammo are made from a very mild form of steel.

Now pick up grandpa’s hammer, you know the one that’s been in the family for fifty years or more, and look at the head. Now how many thousands of nails has it hit? Is it full of a corresponding amount of dings? Firearms and steel cases share the same relationship. Softer materials seldom damage harder materials, period.

I would like to end with my personal recommendation for the use of steel ammo. Interestingly enough it is the same exact advice I give for all ammo… Try a box, if you like it buy a case. Thanks for stopping in and be sure to roast some marshmallows on the dumpster fire below!