Round count for AR reliability testing

[oldtexan]

I am seeking feedback from folks here on how many rds of a particular load they put through a particular .223/5.56mm AR carbine before they deem that AR/load combination to be acceptably reliable for serious use. I have seen the subject of pistol/load reliability testing discussed in various places, but not AR/load testing. I searched the forum but found no threads on this topic.


Would the configuration of the rifle make a difference in the required number of rds to be fired, such as a 16" gun with a mid-length gas system versus a 14.5" gun with the same gas system? Would the choice of .223 ammo versus a 5.56mm load make a difference in the number of rds to be fired during testing(assuming the rifle can safely fire both)? Would the use of the gun for home defense versus LE patrol make a difference to you?

[Unobtanium]

I am seeking feedback from folks here on how many rds of a particular load they put through a particular .223/5.56mm AR carbine before they deem that AR/load combination to be acceptably reliable for serious use. I have seen the subject of pistol/load reliability testing discussed in various places, but not AR/load testing. I searched the forum but found no threads on this topic.


Would the configuration of the rifle make a difference in the required number of rds to be fired, such as a 16" gun with a mid-length gas system versus a 14.5" gun with the same gas system? Would the choice of .223 ammo versus a 5.56mm load make a difference in the number of rds to be fired during testing(assuming the rifle can safely fire both)? Would the use of the gun for home defense versus LE patrol make a difference to you?

I've uncovered issues inherent to the weapon after thousands of rounds.

[oldtexan]

I've uncovered issues inherent to the weapon after thousands of rounds.

Yes, I'm sure that's true. In my opinion, a weapon has to meet some standard of reliability to get put into service and has to continue to meet that standard to stay in service.

Having said that, do you do any reliability testing on an AR/ammo combo before trusting your life to it? If so, what results do you need to see from that testing before you trust that gun/ammo combination?

[rob_s]

If you buy a quality AR from a known entity like Colt, and it makes it through a carbine class with little more than some added lube, I'd consider it good to go.

There is just a mild level of abuse that happens at a class that you can't get toting the gun to the range in a case and shooting it off of a bench. And there are external issues like how a sling mounts up or whether or not you really got the grip screw seated when you changed it that might not get tested at all from the bench.

That said, if I took a Colt 6720 out of the box, zeroed it, and put a total of about 100 rounds through it I'd consider that one mag and that ammo and that gun good to go. I would always be suspicious of an Olympic Arms or any AR with an external piston even if it had 1,000 trouble-free rounds through it.

[TR675]

With AR's I worry more about mags than rifles. I've had at least two brand new mags from reputable manufacturers go TU in a pretty low round count classes.

[Josh Runkle]

With AR's I worry more about mags than rifles. I've had at least two brand new mags from reputable manufacturers go TU in a pretty low round count classes.

I have had a recent similar experience with mags that rhyme with gagpul. I have approx 25-30 mags from that company, about 10 of which are still in plastic wrappers, which leaves 15-20 in rotation. 6 have very serious usage. Another 6 have had moderate usage. The rest are random.

The moderately used ones were all bought when it was "hard" to find mags a year ago. If I have a malfunction with an AR, I stow the mag and then during a break, I take a pocketknife and cut a notch into the bottom of the mag. Anyhow, point being, of those 12 mags that are numbered for training, 2 of the newer mags had like 4-5 notches each, and none of the other mags had any notches. They've been pulled from rotation. It could be absolutely random, but I can look at it either as completely random, or that I'm documenting 1 in 6 mags from that maker having issues, or that I'm documenting 1 in 3 of the recently manufactured mags from that manufacturer as having issues. I run them regularly through 2 different ARs, meaning it's not just one particular gun-mag combo.

Even more interesting to me is that the two with malfunction issues also had feeding issues in my mossberg MVP, whereas none of the other mags have, yet.

My point is that my experience is the same. Newly manufactured mags, reputable manufacturer and issues.

[Chuck Haggard]

Makers build things in batches. Much like when grandma makes cookies. Sometime a batch gets too much or not enough of something and doesn't taste right, or sometimes the batch gets burned.

I would guess that a bad series of MagPul mags were all made in the same run.

[oldtexan]

So is it fair to say that most folks here see reliability testing with an AR as being less critical than reliability testing with an auto pistol, assuming both are to be used for personal protection?

[Wayne Dobbs]

So is it fair to say that most folks here see reliability testing with an AR as being less critical than reliability testing with an auto pistol, assuming both are to be used for personal protection?

I don't know if I'd say it's less critical. I would want at least 280 rounds (10 mags of 28 rounds) to make sure. Start with a clean and lubricated gun and have at it. Shoot at least 20 rounds of single rounds loaded on a magazine so that you test the bolt catch and that there is enough gas to run the bolt carrier far enough, fast enough. If you get through that number of rounds (of what you intend to use for real) with no malfunctions, it should be good. That should show feeding, firing, locking/unlocking, extraction and ejection performance.

Now...all that is valid as long as you have a rifle/carbine built to proper standards and that has been through proper QC/QA testing. If you have a crap bolt carrier and crap bolt and gas key with an unstaked everything on the gun, that test is not valid for the future shooting of the gun. MOST of the AR makers out there (there were over 140 of them at SHOT this year) are only parts assemblers and NOT manufacturers. Words to the wise...

[oldtexan]

I don't know if I'd say it's less critical. I would want at least 280 rounds (10 mags of 28 rounds) to make sure. Start with a clean and lubricated gun and have at it. Shoot at least 20 rounds of single rounds loaded on a magazine so that you test the bolt catch and that there is enough gas to run the bolt carrier far enough, fast enough. If you get through that number of rounds (of what you intend to use for real) with no malfunctions, it should be good. That should show feeding, firing, locking/unlocking, extraction and ejection performance.

Now...all that is valid as long as you have a rifle/carbine built to proper standards and that has been through proper QC/QA testing. If you have a crap bolt carrier and crap bolt and gas key with an unstaked everything on the gun, that test is not valid for the future shooting of the gun. MOST of the AR makers out there (there were over 140 of them at SHOT this year) are only parts assemblers and NOT manufacturers. Words to the wise...

Wayne,

Thanks. How does that compare to your protocol for testing a service auto pistol?