I understand running an AR-15 hard but

[Dallas Jack]

what usually fails when an AR-15 is "run hard". Does the number of failures go up because they are run hot or dry? Do the guns fail just because of hard use?

I am trying to find out what might happen if I had to run my AR-15 hard, hot, or dry. I bought the gun just in case something were to happen like in LA, or New Orleans. But the gun is just a range gun until. And it works very well as a range gun.

Does my thread make sence. Thanks for your help
Dallas Jack

 

[ny32182]

Dry and dirty = more drag on the BCG = possible short stroking.

Hot = Low quality BCG parts would be more likely to crack or work loose.

That said, you would not be "running it hard" in any sort of "SHTF" situation. If you can find anyone who was shooting 1000 rounds+ from their rooftop during any US domestic disaster in history, I would like to hear the story. The only time you will shoot a gazillion rounds with no cleaning or maintenance is when you choose to do so.

 

[dscottw88]

Hope this helps:

http://www.ar15pro.net/2009/11/which-spare-parts-to-get-for-my-ar15.html

 

[LiquidTension]

The only time you will shoot a gazillion rounds with no cleaning or maintenance is when you choose to do so.

Or when the zombies come.

Firing pin, extractor, and springs are the main concerns I think. Mine's never had an issue though, I'll let you know if something breaks

 

[ny32182]

Ah yes, zombies. Forgot about those... consult the documentary "Dawn of the Dead" for details.

 

[MachIVshooter]

I wish I had the money to buy ammo and mags for a torture test and answer your question. I'd love to see how my M15A2C would run with zero cleaning and oiling for thousands of rounds in rapid succession. My guess is it'd hold up fine. Who wants to sponsor a test?

 

[ClickClickD'oh]

In order to make a well maintained AR fail, you will have to dump more ammo through it than you can carry on your person.

 

[Slamfire]

I have a bud who used to work on the small arms rebuild at Annistion Army Depot.

Out of each lot of rebuilt M16's, they pull one and shoot 6000 rounds through it.

The M16 is mounted on a table. I assume it is fired automatically. Between 20 round magazine changes compressed air is blown through the barrel. Everyone wants to go home so the test is conducted as fast as possible.

My friend could not recollect a single instance where a rebuild did not complete the test.

The M16 has been developed to be mechanically highly reliable.

It is still dust sensitive and requires regular cleaning.

 

[rcmodel]

My guess is it'd hold up fine. Who wants to sponsor a test?

The military ordinance department has done the tests several times over through the years.

And very likely the GI's in Iraq & Afghanistan are doing more "run hard testing" right now today then any of use will ever do. Zombies or not.

I keep a spare firing pin, bolt cam pin, 1 extractor & extra springs, & a carrier cotter-key.
Never had any of them break in 40 years though.

It might be simpler to just keep a complete bolt assembly on hand and be done with it, but you will probably never need it.

rc

 

[Zerodefect]

Extractor
Springs, especially the extractor and ejector springs.
Bolt, Ar bolts love to split at the cam pin hole
Cam pin, it can split as well
Magazines, use Pmags
Buffer springs

thats assuming the carrier, buffer, reciever, barrel, etc., are all machined proper.

The AR actually seems to free up a bit when warm/hot. It's Alaska winters it's not fond of. Keep her lubed really wet and a little dirt/carbon should be no big deal.

Check this thread out for some "what kills an Ar in class":
http://www.ar15.com/forums/topic.html?b=3.&f=118&t=360169

 

[taliv]

parts can break, and after a 6000 rnd test, i'd want to replace quite a few of them as part of normal maintenance anyway

but usually the problems people have after running their gun 'hard' for the first time involve thngs like this:

when it heats up, it starts failing to extract... could be due to worn extractor (made with non-standard cheaper material), crappy or worn extractor spring/insert, and usually in combination with a chamber that was not reamed correctly, leaving it a bit tighter than it should be, or God forbid, w/o chrome lining

gas block or tube heats up and moves a bit, reducing the gas flow... improper assembly, machining. that's why they should usually be pinned

bad mags that can't keep up with ROF, but seem fine in slow fire

etc... (sorry, wife calls, gotta go)

 

[d2wing]

Mine had a bad extracter. I bought it from a builder. I dunno what caused it, bad part or abuse.

 

[Bartholomew Roberts]

On ARs, the issue is usually:

1. Bad ammunition
2. Bad magazines
3. Not enough lubrication

That solves 90% of the problems I see. The other problems I see are the rifle gets hot and stops extracting for the reasons taliv outlined above.

Formal training (which is where a lot of failures happen) is really the best investment you can make with an AR. Either you'll be both confident in your rifle and more skilled, or you'll be more skilled and know what needs to be replaced on your rifle.

 

[DougW]

All the reasons listed is why I have spare parts and more than one AR!

 

[SpeedAKL]

On ARs, the issue is usually:

1. Bad ammunition
2. Bad magazines
3. Not enough lubrication

That solves 90% of the problems I see. The other problems I see are the rifle gets hot and stops extracting for the reasons taliv outlined above.

Formal training (which is where a lot of failures happen) is really the best investment you can make with an AR. Either you'll be both confident in your rifle and more skilled, or you'll be more skilled and know what needs to be replaced on your rifle.

This basically covers it. The majority of my jams in an AR have been due to magazines.

 

[Dallas Jack]

ny32182

That said, you would not be "running it hard" in any sort of "SHTF" situation. If you can find anyone who was shooting 1000 rounds+ from their rooftop during any US domestic disaster in history, I would like to hear the story. The only time you will shoot a gazillion rounds with no cleaning or maintenance is when you choose to do so.

I agree with you. In fact I don't know of any situation that someone fired 1000's of rounds in an AR-15 (short period of time) outside of testing.

These are exactly the kind of replys I was looking for. What prompted the question was a discussion on I think AR15.com about the top tier guns working when "run hard" vs AR15's that were considered second tier or lower.

I think what they were refering to as "running hard" was a traning class and or competition.

Thanks for the replies. I'll go read the threads that were linked.
Dallas Jack

 

[briansmithwins]

And then there are just weird failures:

My bolt carrier looked like this after a range trip. I was zeroing, fired about 40 rounds slow fire and this is what I got when I was cleaning it. BSW





Yes, that is a broken gas carrier key bolt. No, I didn't have a spare. I do now.

 

[jpwilly]

I ran my AR-15 somewhat "Hard" to see if it could keep up it was no carbine class treatment but 1500 ish rnds was all I had in my ammo can and shot them all in about 2-2.5hrs at the range. I average 5+ 30rnd mags per session and range took a break every 15min. I didn't lube or wipe down the rifle in any way. There were no failures (I only have 12 mags shot them all & reloaded on the breaks) The rifle got pretty hot (plus it was 100+ out that day) and stayed that way until I finished. The only item that broke was one of the three metal Gas Rings on the bolt the one that broke lost a very small section and the rest remained in place but continued to function. I never fixed it untill just last weekend. I ran this rifle that way (with proper cleanings after range trips for 2 more years) I put three new gas seals just this week...not like I had to but figured for $3 I could make my AR whole again.

This is a DPMS 16" Carbine...I have another DPMS 20 Bull Barrel with much lower round count that has been 100% thus far.

 

[Shawn Dodson]

I suggest replacing the bolt carrier group to improve ruggedness and reliability of lower tier ARs. A new LMT standard bolt carrier group costs about $130.00. See: www.lewismachine.net Swap out the lower tier BCG with the upper tier BCG. Keep the lower tier BCG as a spare, just in case.