MY AR is Having ALOT of trouble! --HELP Please!--

[MoDerN_WarRioR]

Arrgghhh... OK so. I have had previous posts about my AR having some feeding problems. Some people said short stroking, some said its my Mags, some even said my gun could be out of spec. BUT the problems still continue and i think im getting closer to the Root of the beast!

For the specs part of my gun...
- DPMS (Sportical)
- 16" Barrel (1-9) (5.56 Bore)
- PMAG Magazines.
- Shooting .223 PMC Bronze & 5.56 Winchester
- All Stock internal parts
- Gun is Approx 2 years old.
- Cleaned every time after use.

OK so here is what i have discovered today. When i went out shooting today about the first 40-60 rounds shot flawless. No misfeeds and great accuracy. THEN for no apparent reason i started getting misfeeds. Now this has happened to me a couple times in the past but i just recock it and go on. BUT today was Ridiculous! After about the 60th shot or so, EVERY shot i would have to recock the gun like if it was a bolt action! (1 shot.. click... recock... 1 shot... click... recock... ect.) So i was getting very frustrated and started analyzing a little bit.

I noticed on the tip of the BULLET, deep scratch marks. I would slowly release the charging handle allowing the round to extract from the magazine. NOW here is my HUGE million dollar problem "I Think" AS the round contacts the feed ramp and the tip of the bullet starts to move UP the feed ramp, it then will get stuck. (NO LONGER WILL THE FORCE OF THE BUFFER SPRING PUSH THE ROUND INTO THE CHAMBER.) So i would pull the charging Handle AFT again and let the bolt force the round UP the ramp with MORE force.

Once the round is Chambered (for testing reasons) i will then allow the round to extract so i can examine the bullet tip. AND needless to say, the bullet has very sharp deep cuts in it. To me this seems like a HUGE issue that is more than likely the cause to alot of my feed problems i am having. To me visually looking at the ramp i can see a tiny little burr of metal sticking up possibly. NOW... i can see how it would affect the performance EVERY time i shoot the gun; But why would the first 60 rounds shoot flawlessly?? Any thoughts any one? I need to get this fixed ASAP!

Thank you so much for the help! I can upload some pictures if anyone thinks that could be useful!

--Chris

 

[ole farmerbuck]

I'm awaiting replies too.

 

[ol' scratch]

Do you have a camera? Pictures of the problem (bur on the feed ramp) might help. Have you checked your gas tube? Is it misshapen at all? I have read where the carrier key sometimes loosens up and messes up the gas tube.

 

[Bartholomew Roberts]

Pictures would be good. When you clean, are you cleaning out the buffer tube assembly? Also, how long is the buffer spring?

 

[Owen]

If its picking up rounds from the magazine when you fire, its not short stroking. The symptom of short stroking would be bolt override, aka bolt over base.

A short stroke is when the bolt doesn't come back far enough to pick up the next round.

If the bolt is picking up the round from the magazine you are having a fail to feed, which is usally cuased by a lack of energy somewhere.

Tell me how you lube. Has the gun been doing this since you bought it?

 

[halfded]

Did you buy it or build it? M4 feedramps with a standard barrel came to mind when I read the problem, but I'm still a newbie to the platform.

 

[longdayjake]

You may have to post pictures of that burr. AR-15s really really need to be lubed a lot to run well. Especially in the first 500-1000 rounds you fire. Maybe the reason your rifle ran well at first was it had enough lube still on it to make up for the burr in the chamber/ramp. The only thing that the bullet itself should contact with any real force during feeding is the ramp. Other than that you may just need to run your gun dripping wet for the first 500 rounds once you get the burr taken care of. 90% of the time when the gun is ejecting and feeding another round but it doesn't go all the way into battery it is because it just doesn't have enough lube.

 

[Jeremy2171]

I need to know the exact situation the gun was in when it "missfed".

Round fully chambered and you pulled the trigger and nothing happened?

Round fully chambered and you pulled the trigger and it went "click"?

Round not fully chambered, bolt partially open?

Bolt closed on empty chamber and trigger went click?

Let me know...

Lube is irrelevant, ARs will run wet or dry..staggering of gas rings are also not an issue..

I assume it's happening with different mags or only the same mag time after time??

The burr is not a big concern at the moment as you will always get a "scratch" from chambering..

 

[Taurus 617 CCW]

It sounds more to me like a gas problem. The first thing I would check is the condition of your carrier key. If the key screws were not staked or done improperly then you could be losing gas between the carrier key and the carrier. If that's intact then I would start looking at other things.

 

[Al Thompson]

Gun is Approx 2 years old

Bet that it's a weak buffer spring. As Mr. Roberts asked, what's the length?

 

[Jeremy2171]

Buffer spring should NOT be bad after two years and less than 20,000 rounds....

 

[Bartholomew Roberts]

Buffer spring should NOT be bad after two years and less than 20,000 rounds....

It shouldn't be bad after two years of recreational use; but springs are another popular area to cut corners when building ARs. One of the mods here had a brand new rifle that wouldn't work. Problem turned out to be a bad buffer spring in the new rifle.

However, based on the information we have now, it could be a variety of things. I'd agree that it clearly isn't short-stroking. Based on what little we do know, the main places I'd look are:

1. Adequately cleaned and lubed?
2. Correct barrel extension with correct upper receiver?
3. Buffer and/or buffer spring?

 

[Fremmer]

It sounds more to me like a gas problem. The first thing I would check is the condition of your carrier key. If the key screws were not staked or done improperly then you could be losing gas between the carrier key and the carrier.

That's a pretty simple check to do, too.

 

[Mags]

some said its my Mags

Did you really need to capitalize mags? LOL it looks like my nickname now, although I am known to cause a rifle problems.

 

[Frankl03]

I the problem that your not extracting the spent brass? Check the extractor for wear. Wouldn't hurt to replace the extractor and do an upgrade to your extractor.

 

[TimboKhan]

AR-15s really really need to be lubed a lot to run well.

I would disagree with this.

 

[longdayjake]

I would disagree with this.

Okay then try running a brand new one dry for a while and see how long it runs.

 

[Jeremy2171]

Okay then try running a brand new one dry for a while and see how long it runs.

Mine ran fine....one drop of oil on the bolt cam pin and that was it....

They will run dry and should, however super wet just makes the carbon run all over the place and it's just one big black stinky mess....

 

[racky]

is your gastube showing any signs of cracks. check the gasblock and see for any carbon around it. it could explain why it's not cycling.

 

[RyanM]

Gas key is the first thing I'd look at, too. DPMS's staking is horrible, basically just a witness mark. On the bright side, that means you can easily see if it's coming loose.

 

[Zerodefect]

I'm with Jeremy. Not enough info given to diagnose the problem.

It didn't shoot.
Did it chamber a round?
Did the trigger click feel normal?

And Ar's are supposed to be wet, one drop on the cam pin is not enough. The rails, cam pin, rings, need heavy oil. The FP, bolt lugs, trigger group, get light oil.

 

[Jeremy2171]

Beg to differ you CAN run them wet but they don't NEED to be.

Try running wet like you said and it'll be nothing but a sand pit...

Mine ran dry for a year and I put out probably 10,000 rounds with no major stoppages..

 

[longdayjake]

Okay so they will run dry. My experience is that they don't do so well that way until they have been broken in. I run mine pretty dry now, but when it was brand new it needed quite a bit of lube to keep running. Furthermore, I have gotten a few of my friends running correctly just by adding some lube to them.

Mine ran dry for a year and I put out probably 10,000 rounds with no major stoppages..

So what is a minor stoppage and how would you diagnose the cause?

 

[Zerodefect]

I clean mine really often, after every single range trip. But I beat the tar out of my Colt, drop it in rivers, leave it on the ground, shoot in dusty conditions where I wore motorcycle goggles to keep dust out of my contacts.

Prone, urban prone, spetsnaz hatchet weilding backflips, flat on the ground, in rain, snow, muddy hands........etc.

I never really get all that much dirt inside my Colt6920. And it leaks oil like a old Detroit Diesel 16v92ta.

 

[Jeremy2171]

Minor stoppage is something that can be cleared relatively easy usually with just 1 hand.

Major stoppage requires disassembly and/or tools.

My only real problem was a bad mag...dropped the mag...wiggled the two stuck rounds out of the chamber area...grabbed new mag, inserted and continued to rock and roll. Turns out the bad mag had a bent feed lip and had been turned in by someone else as we were shooting off excess ammo. Crushed the mag and threw it away..problem solved.