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Defective Gas Port?

hacabrera071

hacabrera071

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Apr 20, 2019
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McAllen, TX
Guys, I’ve got this new 223 Wylde barrel (very reputable manufacturer, very expensive barrel), that I’m having trouble getting it to shoot accurately and I’m having gas issues with also. I’ve put about 100 rounds thru it and after borescoping it I found the gas port inside the barrel has a dimple on it, the gas port is not perfectly round, see the picture below.

What would you say caused this? Again, new barrel, with only about 100 rounds (77gr sierra matchking). IMO this is a manufacturing defect, I can’t see any other root cause for this problem.
 

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IMO, that dimple looks like an impact mark. There are only two ways I can think of that would cause that at the shop that made the barrel. One would be during the final lapping where the mandrel/rod caught on the port, the other way is a porting tool was used to deburr the gas port and was off center. That burr rolled up on the dimple could be the cause of accuracy loss. Anything you're not telling us? Did a cleaning rod get stuck in the barrel, or you used a metal rod to remove a stuck case? Did the rifle or bullets get dropped on the ground, getting dirt/debris in the barrel?

As far as the hole being out of round, doesn't really look like it to me, it just appears that way due to the curvature of the rifle bore plus "fisheyeing" of the camera lense. I doubt a slightly out of round hole would make any difference with gas flow through the port. Your gas issues are either caused by mis-alignment of the gas block, wrong buffer weight, etc... we would need detailed info on your build to troubleshoot that. With the gas port spanning almost the entire width between the lands, I doubt it's undersized.

If the mark at the gas port is a manufacturing defect, contact the manufacturer. If they're reputable, they'll make it right.
 
hacabrera071 said:
(very reputable manufacturer, very expensive barrel)
Click to expand...
If that's the case then they will replace the barrel, send them a email with the bore scope pics attached and explain what's going on.

Only thing that you're going to achieve by posting on here is a bunch of an speculative opinions that in the end won't get the ball rolling to fix the issue at hand.
 
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Is this your first AR-15?

If you have another, bore scope that and see what that gas port looks like. Like Stavey said, looks like gas port erosion, hot gas eating at the metal.

Did you bore scope before firing your rounds or is this the first time?

Either way probably not the source of your issues unless the gas port is the wrong size.
 
Thanks for your opinions guys, to answer your questions:

-No, this AR has not fallen to the ground/mud nor gotten any strange objects inside.

-I agree that this looks like gas port erosion, but, this amount of erosion at 100 rounds in a top of the line barrel? I’ve got other barrels with 2000+ rounds of the same type and even lot number and those barely show erosion at all.

-This is certainly not my 1sr AR, but must of my experience borescoping barrels has been with my centerfire rifles, which, needless to say have no gas port… that’s the reason I wanted somebody else’s opinion.

-I’ve reached out to the manufacturer, sent them the pictures I got and I’m awaiting on an answer. I’ll let you guys know the outcome.

Thanks!

-Eddie
 
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That is erosion, no part of the manufacturing procces can do that. The manufacture drills a hole there
thats it.
 
That looks like the pattern gas port erosion would make.
But in just a 100 rounds and roll up a burr?
 
accurate obsession said:
That looks like the pattern gas port erosion would make.
But in just a 100 rounds and roll up a burr?
Click to expand...
Agreed. I don't see gas erosion happening that fast or leaving that burr. Broken drill, material defect that broke loose while shooting, off center or broken Burraway (deburring tool for small holes in tight places), sure, I can see all of those happening. Like Big Jake said above, we're all just speculating right now. If the barrel maker takes the barrel back for inspection, maybe @hacabrera071 can add a poll and the winner gets a free internet cookie. I'd like to know what caused that.
 
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whatsupdoc said:
That is erosion, no part of the manufacturing procces can do that. The manufacture drills a hole there
thats it.
Click to expand...

And "drilling holes" can raise burrs. I’m not sure that’s just gas port erosion. It seems like something else might also be going on there. The three pics below show typical gas port erosion and none of them have a raised lip/burr at the apex of the erosion triangle.

gas_port_erosion_003-2665676.jpg



gas_port_erosion_002-2665675.jpg



gas_port_erosion_001-2665674.jpg



The next picture shows a virgin barrel with a burr at the 3 o’clock position.

gas_port_burr_001b_resized-2665673.jpg



The OP’s barrel almost looks as if (not saying that’s what it is) the barrel had a burr in the 12 o’clock position that got “pushed” forward along with the erosion. It's certainly something atypical, whatever it is.

op_gas_port_03-2665703.jpg



OP, who was the manufacturer? Did you buy the barrel directly from the manufacturer? Can you take some straight bore-scope pics (without the mirror) from both ends of the barrel?

.....
 
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hacabrera071 said:
-This is certainly not my 1sr AR, but must of my experience borescoping barrels has been with my centerfire rifles, which, needless to say have no gas port… that’s the reason I wanted somebody else’s opinion.
Click to expand...
Hold up, this is in a rimfire? If so this is double or even triple weird.
 
Holy shit, someone actually using a borescope as intended (instead of using it as an excuse to go unnecessarily bananas when barrel cleaning). I wasn't sure I'd live to see it.

That said, the OP's pic looks more like what you see with a baffle strike than erosion... I'd bet there was a burr leftover from drilling the gas port hole, and the first round or so "customized" it further...

Well, now you know why it didn't shoot for shit, doh. I'd ask/expect a replacement from the manufacturer, if you get any lip, maybe remind them about the 100 rounds of 77gn (and your time/gas) down the drain, bummer.
 
BuildingConceptsllc said:
I thought he just meant "with my bolt guns". He said it's an ar15 and a 223 so I don't think he meant that to say this was a rimfire rifle, though I guess it is possible.
Click to expand...
My apologies guys... I meant to say my experience borescoping was with my centerfire bolt guns.... This is the first time I use it to borescope one of my centerfire gas guns, and I'm glad I did.

I'll keep you posted on what the manufacturer says, should be a fun ride!

Thanks again!

-Eddie
 
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Molon said:
And "drilling holes" can raise burrs. I’m not sure that’s just gas port erosion. It seems like something else might also be going on there. The three pics below show typical gas port erosion and none of them have a raised lip/burr at the apex of the erosion triangle.

gas_port_erosion_003-2665676.jpg



gas_port_erosion_002-2665675.jpg



gas_port_erosion_001-2665674.jpg



The next picture shows a virgin barrel with a burr at the 3 o’clock position.

gas_port_burr_001b_resized-2665673.jpg



The OP’s barrel almost looks as if (not saying that’s what it is) the barrel had a burr in the 12 o’clock position that got “pushed” forward along with the erosion. It's certainly something atypical, whatever it is.

op_gas_port_03-2665703.jpg



OP, who was the manufacturer? Did you buy the barrel directly from the manufacturer? Can you take some straight bore-scope pics (without the mirror) from both ends of the barrel?

.....
Click to expand...

This is a Proof CF barrel, got it brand new from Brownells (iirc). I'll take some straight borescope pictures and update you guys here.
 
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Typical gas erosion in a high end stainless barrel , happens much quicker than you’d expect.
 
hacabrera071 said:
This is a Proof CF barrel, got it brand new from Brownells (iirc). I'll take some straight borescope pictures and update you guys here.
Click to expand...
See that's what I'm talking about... You could have just said that from the get-go,

Proof 100% warranties their barrels at .75 MOA or less, send that fucker back.
 
Here is a WOA gas port at 42 rounds.

IPC_2022-04-12.02.40.46.8340.jpg


Here it is unfired.

IPC_2022-04-08.13.37.26.2320.jpg


It has not changed hardly at all since these pics. I have about 100 rounds through it so far.

It is gas erosion and thats it. Nothing more.
 
Molon said:
That burr at the apex of the erosion triangle is not typical at all.

...
Click to expand...
I’m not convinced it’s a bur , borescopes make things look strange , I’ve seen fuzz look like cracks in the bore.
Gas erosion is unpredictable and quite variable in barrels but my understanding is that it’s usually worse in stainless cut rifled barrels, happens quickly ( usually terrifying the owner)then pretty much tapers off and does not continue at the same rate. And does not have an effect on accuracy usually (anything is possible)
 
Can you feel it with a tight fitting patch as you pass it through the barrel? I would do as Molon said and take the mirror off the bore scope and get some pics from both ends of the port. That will tell you what this is.
 
Talked to the manufacturer (Proof), they agreed right away the rolled burr is not normal and offered to exchange the barrel for a new one… the raised edge was the part that caught their attention and which they mentioned shouldn’t have been caused by gas port erosion, so they happily jumped to turn things around, great customer service in my experience! Thanks y’all!
 
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hacabrera071 said:
Talked to the manufacturer (Proof), they agreed right away the rolled burr is not normal and offered to exchange the barrel for a new one… the raised edge was the part that caught their attention and which they mentioned shouldn’t have been caused by gas port erosion, so they happily jumped to turn things around, great customer service in my experience! Thanks y’all!
Click to expand...
So much for the tards who were stating that this was normal gas port erosion.
anim_rofl2-1959491.gif


...
 
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hacabrera071 said:
Talked to the manufacturer (Proof), they agreed right away the rolled burr is not normal and offered to exchange the barrel for a new one… the raised edge was the part that caught their attention and which they mentioned shouldn’t have been caused by gas port erosion, so they happily jumped to turn things around, great customer service in my experience! Thanks y’all!
Click to expand...
Good to hear you're being taken care of!
 
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hacabrera071 said:
Talked to the manufacturer (Proof), they agreed right away the rolled burr is not normal and offered to exchange the barrel for a new one… the raised edge was the part that caught their attention and which they mentioned shouldn’t have been caused by gas port erosion, so they happily jumped to turn things around, great customer service in my experience! Thanks y’all!
Click to expand...

Posts some pics of the gas port on your new barrel when it arrives!

...
 
hacabrera071 said:
Guys, I’ve got this new 223 Wylde barrel (very reputable manufacturer, very expensive barrel), that I’m having trouble getting it to shoot accurately and I’m having gas issues with also. I’ve put about 100 rounds thru it and after borescoping it I found the gas port inside the barrel has a dimple on it, the gas port is not perfectly round, see the picture below.

What would you say caused this? Again, new barrel, with only about 100 rounds (77gr sierra matchking). IMO this is a manufacturing defect, I can’t see any other root cause for this problem.
Click to expand...
I had the same type of pattern on my gas port from a LaRue Tactical Barrel.
After about 30 rounds through it I cleaned it and every time my Tipton rod and Jag got to where the Gasport was I could fill it catching and making a slight tick noise.
Then I bore scoped it and found this.

Thankfully they offered to replace the barrel for me and I told them to make it quicker I could just do it myself and not only did they send me the barrel but they sent me a new gas block gas tube and one of their Barrel nuts along with their special tool to change the barrel and no extra charge just for the inconvenience.

I was still averaging 0.5-in groups but it just bugged me because the more I shot the larger it got.

I can tell that as the bullet passed over the high spot it was waging the bullet downward so from that point forward there was no copper fouling on that particular land in the barrel because the copper wasn't touching it.

I know this is an old thread I just never ran into anyone else that had the same problem I did so I wanted to make a comment.

Hope you all are having a lovely day
 

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Gas port erosion is a part of life if you shoot a gas gun. They all do it - some in different fashions - and at different rates. And all 416-R barrel blanks are apparently not equal.

Have you ever had a new, fancy SS barrel that shoots absolutely lights out initially - And then shoots like crap?!? Then, after 200 or so frustrating rounds, it again becomes a shooter?

When the barrel is new and this gas port erosion first begins, it is not always a "smooth" process. Occasionally, the first thing that happens is a sizable chunk of barrel detaches from the forward edge of the gas port. My personal (and irrelevant) term for this is "chunking". A big chunk breaks off! The forward edge of this missing chunk catches a sizable amount of bullet jacket, creating a high spot in the barrel and produces strip of copper down the bore you can usually see in good light without magnification at the crown. And accuracy immediately goes to hell.

Does this mean you and the barrel are doomed? No. After about 200 (correct to one significant digit) rounds, this otherwise perfect barrel will begin to produce those sub-MOA groups with match ammo you were rightfully expecting when you shelled out the big bucks in the first place.

I spend a lot of time using a borescope when breaking in a barrel and with every subsequent cleaning. This unhappy phenomena seems to be peculiar to SS barrels. I've never once observed this with 4150 chrome lined barrels.

And not ALL SS barrels! For example, I've never seen it, even once, with a Bartlein or Proof SS barrel. But, based on your images, you have.

My suggestion, If you want a new barrel - contact Proof Research. They'll take care of you.

An alternative idea: Go shoot steel hard for a couple hundred rounds, enjoying yourself. Clean the barrel and check out the gas port with the borescope. My bet is all will be well.
 
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