Shooting Steel Cased Ammunition In Your AR-15

If you’ve been shooting for very long, especially as ammunition prices have risen in the past two years, you’ve no doubt noticed the large amount of inexpensive steel cased ammunition available. It’s hard to pass it up: prices for steel cased ammunition are almost half that of traditional brass cased ammo. But take it out to the range and it won’t be long before you hear the “tsk tsk” of other shooters, shaking their heads and commenting on how horrible it is to run steel cased ammunition in an AR-15 style rifle.

But is steel cased ammo really so bad? Is it safe to shoot steel cased ammunition in your AR-15?

Let’s own up to a few facts first. Discount steel cased ammunition is, in general, dirtier and smellier than mil-spec Lake City manufactured 5.56 NATO ammunition. It’s not quite as accurate, but most shooters won’t miss a half-MOA here or there.

Now, on to some myth busting. Modern production steel cased ammunition is NOT corrosive, even when berdan primed. It won’t destroy your extractor, and it won’t accelerate wear on your bore. The ferrous bi-metal jackets found on most steel cased ammunition will not damage the rifling of your AR, and are perfectly safe to use on any rifle rated backstop.

So what do you need to do to run steel cased ammunition in your AR-15? First, you’ll need to make sure that your AR-15 is very well lubricated. Dripping wet some might say; especially the bolt carrier group. You’ll need to clean your rifle more often when shooting steel cased ammunition, at least once every 500 rounds, although 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 like M-Pro 7 along with a synthetic lubricant. Make sure to throughly clean your bolt, paying close attention to the bolt face and extractor. It’s usually a good idea to remove the extractor to clean underneath as well. You’ll also need to make sure to thoroughly clean the chamber, so picking up an M16/AR-15 chamber brush is a good idea.

Steel cased ammunition is generally loaded lighter than standard military loads, so it’s important that your gas system runs well. Some AR rifles have smaller gas ports and won’t cycle well with the reduced power loads found in some steel cased ammunition. If you find this is a problem, switching to higher power steel cased ammunition such as our Wolf Military Classic may resolve this issue. Using a lower weight buffer or a lighter buffer spring can also be necessary when shooting steel cased ammo.

Steel cased ammunition is available with three different types of coatings. Older steel cased ammunition was usually found with a lacquer finish to help prevent rust and corrosion of the case. Brown Bear ammunition still uses this coating. Some AR-15 rifles begin to have problems with lacquer coated steel cased ammunition as heat begins to build up. Switching to modern production steel cased ammo with polymer coatings sometimes alleviates this problem, but in other cases it is necessary to use zinc coated steel cased ammunition such as Silver Bear.

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 ammunition to get stuck as the metal heats up. Even Wylde chambers and other .223/5.56 hybrid chambers have been known to have issues with stuck spent steel casings. Stick with a true 5.56mm chamber and, as we mentioned above, remember to scrub the chamber out every 500-1000 rounds to ensure reliability.

Steel cased ammo may have gotten a bad rap in the past, but there’s 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 rifle, but you know better now. Save some money when plinking and try out steel cased ammunition. Most AR-15 rifles run it just fine with no problems at all.