Throwback Thursday: Shooting Steel-Cased Ammo In Your AR-15 By: CTD Blogger

Person shooting a semi-automatic AR-15 assault weapon rifle at an outdoor gun range

Although it is no longer imported from Russia, a large amount of steel-cased ammunition is still available. It is hard to pass it up — prices for steel-cased ammo are not what they once were, but it is often cheaper than that of traditional brass-cased and potentially collectible. Either way, when you take some steel case ammo to the range for your AR, it won’t be long before you hear the “tsk-tsk” of other shooters commenting on how horrible it is to run steel-cased ammunition in an AR-15 style rifle. Is steel-cased ammo really so bad? Is it safe to shoot steel-cased ammunition in your AR-15?

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Busting Myths

Picture shows a steel-cased .223 Remington round.
Steel-cased ammunition has gotten a bad rap. In truth, there’s nothing wrong with it.

Let’s own up to a few facts. In general, steel-cased ammo is dirtier and smellier than Mil-Spec Lake City manufactured 5.56 NATO ammunition. Further, it is not quite as accurate. However, many shooters won’t miss a half-MOA here or there, especially for casual training or plinking.

Now, on to some myth-busting. Modern production steel-cased ammo is not corrosive, even when Berdan primed, and it will not destroy your extractor. The ferrous bi-metal jackets found on most steel-cased ammo will not damage the rifling of your AR and are perfectly safe to use on any rifle-rated backstop.


AR-15 M-15 on Wood Background
It’s perfectly fine to run steel-cased ammunition in your AR-15 rifle.

Dripping Wet

What do you need to do to run steel-cased ammunition in your AR-15 successfully? First, you will need to ensure your AR-15 is well lubricated. Dripping wet some might say — especially the bolt carrier group. You will need to clean your rifle more often when shooting steel-cased ammo — at least once every 500 rounds. However, you could get away with letting it go for up to 1,000 rounds.


Because steel-cased ammunition results in more carbon build-up, it’s important to use a high-quality solvent such as M-Pro 7 along with a synthetic lubricant. Thoroughly clean your bolt, paying close attention to the bolt face and extractor. It is usually a good idea to remove the extractor to clean underneath as well. You will also need to clean the chamber with a good M16/AR-15 chamber brush.

Modern Coatings

Steel-cased ammo is generally loaded lighter than standard military loads, so it is important that the AR’s gas system runs well. Some AR rifles have smaller gas ports and will not cycle well with the reduced-power loads found in steel-cased ammunition. If this becomes a problem, switch to brass-cased ammo. Using a lower-weight buffer or a lighter buffer spring may also be necessary when shooting steel-cased ammo.

Steel-cased ammunition is available with three different types of coatings. To help prevent rust and corrosion of the cartridge case, older steel-cased ammo is lacquer finished. Brown Bear still uses this coating. As heat begins to build, some AR-15 rifles start to have problems with lacquer-coated, steel-cased ammo. Switching to modern production steel-cased ammo with polymer coatings sometimes alleviates this problem. In other cases, it may be necessary to use zinc-coated steel-cased ammo such as Silver Bear.

Steel cased ammunition in ammo can
Steel-cased ammunition is a great resource for inexpensive shooting.

5.56 NATO vs. .223 Remington

The best way to avoid extraction problems due to stuck cases is to use an AR-15 with a 5.56mm chamber. Differences in headspacing between 5.56 and .223 chambers can cause steel-cased .223 or 5.56mm ammo to get stuck as the metal heats up. Even Wylde chambers and other .223/5.56-hybrid chambers occasionally have issues with stuck spent steel casings. Stick with a true 5.56mm chamber and, as mentioned, and remember to scrub the chamber every 500 to 1,000 rounds to ensure reliability.

Steel-cased ammo may have gotten a bad rap, but there is really nothing wrong with it — so go for it! Some AR snobs may sneer at the mere thought of running steel-cased ammo through their precious rifles, but you know better now. Save money when plinking and try some steel-cased. Most AR-15 rifles run it just fine with no problems at all.

Do you run steel-cased ammunition in your AR-15? What have you found that works best? Share your tips and tricks with others in the comment section.

Editor’s note: This post was originally published in May of 2010. It has been completely revamped and updated for accuracy and clarity.