M4 variant AR15 having extraction issues

[Batman]

I've got an AR15 in M4 configuration that's been having issues with extraction. I thought it may have been the extractor, but the heads are getting chewed up to where I'm using a rod to pop the empty case out of. I'm assuming it's something grabbing the case in the chamber. I figure I've got three options;

1. Get the chamber reamed by a gunsmith to make sure it's within spec.
2. Replace the barrel, which has it's own dilemmas. .223? 5.56? .223 Wylde?
3. Just get a new complete upper and call it a day.

Thoughts?

 

[RustVendor]

all one kind of ammo or every ammo youve tried? whats the brand of the barrel and ammo?

 

[Batman]

Multiple different ammo having similar issues. Everything from surplus to American Eagle to Wolf Gold.

 

[RustVendor]

Multiple different ammo having similar issues. Everything from surplus to American Eagle to Wolf Gold.

who makes the barrel/upper? has it always done this or just started?

 

[Batman]

There's no markings on the barrel other than 5.56x45 1/9, and the upper only has a square mark above the forward assist. Weird part is that the gun's been running fine for years with no issues, but last time I took it out, I had the same issue, so I ran everything through a large ultrasonic cleaner, only to have the same problem again.

 

[RustVendor]

so if it's already run well it's likely not the chamber/barrel because it's not gonna shrink. It could be gas related, the tube could be clogged or gas block misaligned. You can test that by taking off the muzzle device, blocking the barrel chamber with something and putting air down the barrel and seeing if it's coming out the tube, it should be a good amount of air not just a little bit. The other part of the gas system is the BCG, the gas rings could be shot or it could also be clogged, you can take it apart and look at the rings and see if it's clogged, easiest just to throw another BCG in and see if that fixes it.

 

[Hamburger Monster]

Typically when the rim is getting messed up during extraction it's because the chamber pressure is too high when the bolt is moving back. Basically the bolt is starting too early.

You have too options usually. Reduce the gas on the gas tube, like using an adjustable gas block, or by increasing the buffer weight to delay the opening until the pressure has dropped enough to release the case grip on the chamber

 

[AR15barrels]

I've got an AR15 in M4 configuration that's been having issues with extraction. I thought it may have been the extractor, but the heads are getting chewed up to where I'm using a rod to pop the empty case out of. I'm assuming it's something grabbing the case in the chamber. I figure I've got three options;

1. Get the chamber reamed by a gunsmith to make sure it's within spec.
2. Replace the barrel, which has it's own dilemmas. .223? 5.56? .223 Wylde?
3. Just get a new complete upper and call it a day.

Thoughts?

Have you mechanically cleaned the chamber with a chamber brush?
The ultrasonic sometimes wont free stuff that can cause this.

How many rounds does the barrel have through it?
Did you shoot a lot of steel cased ammo earlier in the life of the barrel?
Does this barrel have a front sight base that's cross pinned to the barrel?
Have you pulled the gas tube out and inspected the mushroom for wear?

 

[Plenty_Pack_556]

There's no markings on the barrel other than 5.56x45 1/9, and the upper only has a square mark above the forward assist. Weird part is that the gun's been running fine for years with no issues, but last time I took it out, I had the same issue, so I ran everything through a large ultrasonic cleaner, only to have the same problem again.

Ultrasonic cleaners eat aluminum. Best not to use alum in Ultra sonic cleaners. I put a 7075 Aluminum part in my ultrasonic cleaner.

1st time around, it made it really dry and a bit gritty. 2nd time around, it made small pockmarks and extremely small pin hole type mark on some areas. These were cleaned in no solution, just clean water.

Unless you really know what temp water, what water pH, what solution, how long timed, change in variable settings, etc., you should never put aluminum in ultrasonic cleaners. Without knowing any of these factors and using ultrasonic on alum like you would for steel, you can almost bet you lost tolerances somewhere.