Double Feed Issue - Issue Caused by Paint Interior?

[medved11 71]

I was at the range yesterday with a friend who brought a new 5.56 AR with him (I forgot the make/model).

 

Anyhow, he kept having repeated issues with double feed and even one triple feed jams (which required mortaring the gun and a dis-assembly to clear).

 

I'm not an AR expert, but I'm thinking that the problem may the result of the interior of the upper receiver having been painted when it was Cerakoted (that extra .001 inch of paint causing friction/drag). Does this seem plausible?

 

The problem seemed to be temporarily resolved when the BCG was coated in CLP; however, after a few rounds, the feeding issues would start again Is there anything else that he should look at inside of the upper or the BCG in terms of what might be causing this issue? 

[High Exposure 5,684]

Was the double feed 2 live rounds, or one live and one spent casing?

[medved11 71]

It was a mix, which was a weird thing to me.

 

There would be a double feed of a live round behind a spent round which was cleared, followed by a double feed of two live rounds. The triple feed was a spent round with two live rounds jammed. To clear that one, I have to mortar the gun to get the bolt to spit out the spent brass - I then had to push down on the upper and pull the rear pin to relieve enough pressure to drop the magazine and clear the two live rounds

 

I hope that makes sense.

 

 

Sent from my iPhone using Tapatalk

[medved11 71]

I'm not sure if it's relevant but he was using a Hexmag and Freedom Munitions ammo

 

 

Sent from my iPhone using Tapatalk

[medved11 71]

What makes me think that it might be the paint is that the problem went away as long as the gun was running wet

 

 

Sent from my iPhone using Tapatalk

[fatty 241]

Your friend didn't try a different mag?  maybe a pmag?  I can't see why the paint would cause a double/triple feed

[medved11 71]

He only had the Hex mags. I was shooting a .308, so I couldn't give him one of mine to try.

 

It was a really weird thing. I've never seen a rifle have so many consistent jams.

 

Maybe an issue with ammo? I know that he had one round that seemed like the bullet was not properly crimped into the case. I discounted it at the time because I thought that it may have been the result of the misfeed

 

 

Sent from my iPhone using Tapatalk

[High Exposure 5,684]

Generally 2 live rounds is a mag issue.

 

One live and one spent is an extractor, gas issue, or mag.

[medved11 71]

I'll ask if he's got other mags to try. He had two different Hex mags with him yesterday.

 

Sent from my iPhone using Tapatalk

[raz-0 1,265]

HE is mostly right. One spent sitting nicely on the bolt face would be an ejector issue. Partially extracted would be extractor. 0.001" is the thickness of properly applied cerakote. Who knows what's on there.

 

It's entirely possible it is slowing things down, and once you slow things down mags can behave oddly. They are designed with tension to behave properly given a certain amount of oomph. Hex mags put most of the tension to the rear, and one of the symptoms of slow cycling in semi autos in general is dragging the next bullet in the mag forward while the top most round is being stripped.

 

Verify you ejector and extractor are good. If it were mine, beyond that my first step would be a moly bearing dry lube for the inside of the upper receiver. I have stuff called dry slide.

 

I suppose that remdrilube is another option.

 

That'd be my first try.

[medved11 71]

HE is mostly right. One spent sitting nicely on the bolt face would be an ejector issue. Partially extracted would be extractor. 0.001" is the thickness of properly applied cerakote. Who knows what's on there.

 

It's entirely possible it is slowing things down, and once you slow things down mags can behave oddly. They are designed with tension to behave properly given a certain amount of oomph. Hex mags put most of the tension to the rear, and one of the symptoms of slow cycling in semi autos in general is dragging the next bullet in the mag forward while the top most round is being stripped.

 

Verify you ejector and extractor are good. If it were mine, beyond that my first step would be a moly bearing dry lube for the inside of the upper receiver. I have stuff called dry slide.

 

I suppose that remdrilube is another option.

 

That'd be my first try.

Thanks - I've passed the info along. I'll post an update once he has a chance to check things out and hit the range next weekend

 

 

Sent from my iPhone using Tapatalk

[High Exposure 5,684]

I have never ever seen an ejector go bad, but I have seen one bolt (Daniel Defense) that had a bad ejector from day 1.

 

Bolts generally shear a lug or crack at the cam pin hole well before the ejector craps out.

 

Bad extractors are another story and I have seen plenty of them.

 

I would try different mags first.

 

After that I would try a new BCG that I knew to be reliable.

[mipafox 438]

In decreasing order of likelihood:

 

1. He bought a shitty gun.

2. Mag issue. Tag the mag with a sharpie or a sticky target bullet hole cover and measure the feed lips when you get home (or him). Not to see if you can keep using the mag, you throw out suspect mags, they are disposable. Just to check if you found the problem.

3. No, not PMAGS for troubleshooting. They are not as reliable as GI mags. Troubleshoot with GI mags.

4. Weak ammo plus shitty rifle can cause multiple feeds if the rifle is less shitty than ordinary shitty rifle.

 

You can troubleshoot shitty rifle, but I never bought one, and it's better just to sell it IMO.

[raz-0 1,265]

I have never ever seen an ejector go bad, but I have seen one bolt (Daniel Defense) that had a bad ejector from day 1.

 

Bolts generally shear a lug or crack at the cam pin hole well before the ejector craps out.

 

Bad extractors are another story and I have seen plenty of them.

 

I would try different mags first.

 

After that I would try a new BCG that I knew to be reliable.

I'm agree, but my take on it was this is a new gun or newly ceracoated, which could mean disassembled into very small parts by someone who is not the best armorer. DOA ejector was primarily where I was aiming with that suggestion. I'm with you that they don't tend to go bad but mostly get assembled or reassembled incorrectly.

 

It would help to know if they were staying part way in the chamber.

[High Exposure 5,684]

Mipa I'm with you except for the GI Mags. In my experience, Pmags have been superior to GI Mags for reliability and durability.

 

After bad mags, I am guessing low quality gun/parts - specifically a crappy BCG.

[medved11 71]

Thanks for the info - I'll pass it along to see if he can figure this out.

 

The gun is made by Anderson. What's the general opinion regarding their quality?

 

 

Sent from my iPhone using Tapatalk

[MidwestPX 172]

I'll second/third the recommendations to try different mags and a different BCG, preferable mags and a BCG known to work properly in another rifle. If a different mag resolves the problem, try the Hex Mags in a different rifle and see if you can replicate the issue. Same for the BCG. If a BCG swap has the rifle running right, try the original BCG in a rifle that runs properly and see what happens. Double/triple feeds in my experience almost always trace back to either the mags or the BCG.

[medved11 71]

I'll see if he's knows anyone that can loan him a BCG to test. The gun in question is his first AR, so he probably doesn't have any spare parts built up yet. He's going to try and borrow a different magazine as well

 

 

Sent from my iPhone using Tapatalk

[mipafox 438]

Mipa I'm with you except for the GI Mags. In my experience, Pmags have been superior to GI Mags for reliability and durability.

 

After bad mags, I am guessing low quality gun/parts - specifically a crappy BCG.

Not going to turn this into a pissing match, I'll just leave it at this. Durability, yes. Reliability, no. Of course, that can change over time with "durability." They have more stack issues, especially in full auto, or when loaded with "jam" loaders (speed stripper clip loaders).

[High Exposure 5,684]

Fair enough. Agree to disagree.

 

That is directly counter to my experience and the experience of all of those that I know and trust.

 

In any event, mags are wear items and should be given hammer therapy when they stop working whether they are GI, PMag, ARC, HexMags, Lancer, etc...

[medved11 71]

I found a reliable 10 round AR mag for us to try with some quality ammo.

 

I'll post an update once we try this out

 

 

Sent from my iPhone using Tapatalk

[Lalo 13]

I stopped reading when you mentioned he was using Hex mags... Try PMags and factory Ammo, not reloads.

[Eric. 9]

Feed lips speading too much on the mags?

 

Open the receiver and cycle the bcg by hand. It should move freely without binding and no excessive side play.

 

Try a GI steel mag. More importantly, only change on thing at a time, to isolate the issue.