AR15 Function Testing

AR15 Function Testing
By Ben Kurata

Wilson Combat 6.8 Spc Ar15 M4 Variant
Wilson Combat 6.8 SPC Ar15 M4 Variant
Action Target

Provo, Utah –-(Ammoland.com)- 12 gauge pump shotguns have been part of the Law Enforcement arsenal for a long time, and patrol rifles are becoming more commonplace, with the AR-15, M4 or some variant being the most common.

It is no secret that I am a proponent of the patrol rifle, as anything a handgun can do, a rifle can do better, and from a longer distance.

As more and more of America’s LE Officers are being confronted with rifles (the semiauto AK-47, SKS and variants being the most common), it’s time to rethink operational priorities.

Early in my LE career, when the 12 gauge pump was the standard LE long gun, you could always tell the rookies (myself included) from the veterans. The rookies would go dashing off to the scene of a shots fired or man with a gun call, where the veterans would always take the few seconds to get to the trunk, take out the 12 gauge pump, and maybe grab a pocketful of extra buckshot or slugs.

Therein lies a lesson:

Don’t take a handgun to a long gun fight.
Now, I can hear the cyber moaning and wailing already as I type this. “My department will never allow… My Chief will never go for…. The community will be in an uproar….”, etc., etc. All I can say is, I never thought I’d see the day when fully geared up NYPD ESU Officers would be visibly present at major infrastructure locations in Manhattan, wearing M4’s, full raid vests including a Kevlar lid, but that day is here. If you don’t ask, you don’t get. I’m not making light of any department’s struggles with getting a patrol rifle program accepted and funded, as I have assisted many departments with getting their programs off the ground and know how difficult it is. My point is, more and more of America’s finest are being gunned down with a rifle chambered in 7.62 X 39 COMBLOC. When facing a rifle with a 30 round box magazine attached, even your favorite high capacity 9mm / .357 SIG / .40 S&W / .45 ACP is not “enough gun”. You need a long gun.

Maximizing Patrol Rifle Reliability:
The AR-15 / M4 (or some variant) is the most common patrol rifle, so let’s focus on it first. First, the direct gas impingement system invented by Eugene Stoner is an inherently high maintenance system. Anyone who has spent the better part of an evening attempting to scrape the last bit of carbon fouling off the bolt tail or the corresponding recesses in the bolt carrier knows what I am talking about.

Which brings up an operational question: How often & who will perform routine preventative maintenance on the issued rifles? The Stoner system also requires a fair amount of lubrication, particularly once you start firing it, as the gas blowing back onto the bolt has a tendency to burn off any lubrication on the bolt’s gas rings quickly. Here in the Southwest, where the air temperatures have been above 100 degrees F all week, the temperature inside a police cruiser’s trunk is hot enough to bake a pizza. Almost every patrol rifle that I have seen taken directly out of a cruiser’s trunk has been bone dry and badly in need of lubrication. Routine maintenance is critical if the rifle is going to function reliably.

Another area to look at closely is the patrol rifle’s magazines. I covered magazine function checks in a previous article, but suffice it to say that just previous to the last national high capacity magazine ban, anybody with aluminum sheet metal and a spot welder was cranking out AR-15 magazines. Even the original mil-spec magazines were intended to be used just a few times, then discarded. I personally run only stainless steel mags with a military phosphate or nitride finish. If a rifle magazine is not feeding properly due to a split back seam (common) or bent feed lips, take it out of inventory and destroy it.

Patrol Rifle Function Test:
Make certain that there is no live ammunition in the rifle or associated magazines. Again, I find a physical chamber check going up through the mag well faster and more accurate than a visual check.

  1. Let the bolt go forward.
  2. Insert a mag and lock it into the mag well.
  3. Pull back smartly on the charging handle. The bolt should lock to the rear. If it does not, check the orientation of the magazine springs. Unlike most pistol magazines, the spring in most AR-15 mil-spec mags is attached to the follower and is difficult to orient backward. But, if it is humanly possible…
  4. Push the charging handle forward into the locked position.
  5. Push the magazine release button. The magazine should fall free under its own weight. If it does not, it could be due to either a bent magazine tube OR the magazine release catch has been screwed too far into the mag well. If you have the same problem with all of your mags, try backing off the catch arm one full turn and repeat the test.
  6. Slap the bolt release. The bolt should fly forward sharply and lock up into the rear of the barrel.
  7. Point the muzzle in a safe direction and put the safety on “Safe”. Pull the trigger, hard. Nothing should happen.
  8. Put the safety on “Fire”. Press the trigger. You should have a normal trigger press and hammer fall. Keep the trigger depressed.
  9. Rack the charging handle.
  10. Let the trigger go forward slowly until you hear and feel the very loud disconnector reset.
  11. Press the trigger again.
  12. Attempt to put the safety on “Safe”. With the hammer down on an AR-15 and variants, the safety cannot be put on safe.
  13. Repeat for all remaining magazines.

*This is the first entry in a 2-part series. Click here for the second installment.

About Action Targets:
Action Target is a privately owned business headquartered about 40 miles south of Salt Lake City in Provo, Utah. For the last 20 plus years, Action Target has been the dominant force in shooting range equipment design and manufacturing for law enforcement, military, and commercial ranges around the world. We are proud of our commitment to deliver advanced firearms training products that help prepare our men and women in uniform for the heroic job of defending our safety and our freedom. Visit: www.actiontarget.com

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