AR gas port question

[fatelvis]

This borescope pic from my PSA stainless 18” upper in 224 Valkyrie shows that is partially blocked. I use medium charges of CFE223 and a 80SMK. It shoots wonderful groups and functions fine.
My question is: will it eventually plug up completely? If so, Is there a good way of cleaning it without removing my gas block? Thanks for any and all info guys!

 

[Nightraider]

Nope it won't plug, 25,000psi has a way about cleaning that out

 

[Sniper338]

Prolly just in your sweet spot. No way itd plug. Only way I know to clean it is to squirt strong cleaner in through the gas block to eat at it, but theres disassembly gonna be required, and good cleaning after that.

I wouldnt worry about it and clean as normal if it shoots anyways.

 

[Rustytigwire]

Great pic. Shoot till it acts up, look there first. What powder/ loads do you suspect caused this?

 

[fatelvis]

I've shot nothing but 26.2grns CFE 223 and a 80SMK seated to 2.26" since load workup. About 400 rounds +/-.

 

[bobcat93]

Anything - lead, carbon, copper..if its in their its getting blow torched out of the way .
No worries mate

 

[Coyotefurharvester]

I thought that's what the long pipe cleaners were for.

 

[jelenko]

Just to confirm, the pic was taken after a range session and before any cleaning?

 

[ELR LVR]

I had to get adjustable gas blocks to turn down the Overgassing problems
At least ya don't have to do that.
Or do you run an adjustable?
If so, maybe the hole built up to just the same flow rate the gas block volume will allow?

 

[hoz53]

View attachment 1172799 This borescope pic from my PSA stainless 18” upper in 224 Valkyrie shows that is partially blocked. I use medium charges of CFE223 and a 80SMK. It shoots wonderful groups and functions fine.
My question is: will it eventually plug up completely? If so, Is there a good way of cleaning it without removing my gas block? Thanks for any and all info guys!

i use the borescope to line up the hole in the gasblock to hole in barrel—if you did have to clean it - would be a quick easy job.

 

[Jeff Porter]

Looks like residual cleaning materials. Do you use a spray foam cleaner like Wipeout ?

 

[MGYSGT]

Isn't it something that the whole is right in the land and he reports it shoots great groups. I have one the same way. I doesn't seem to hurt a thing.

 

[fatelvis]

Just to confirm, the pic was taken after a range session and before any cleaning?

That was after cleaning the bore

 

[fatelvis]

I had to get adjustable gas blocks to turn down the Overgassing problems
At least ya don't have to do that.
Or do you run an adjustable?
If so, maybe the hole built up to just the same flow rate the gas block volume will allow?

It is not an adjustable gas port

 

[fatelvis]

Looks like residual cleaning materials. Do you use a spray foam cleaner like Wipeout ?

No, I use Eliminator and occasionally Iosso

 

[simo hayha]

What bore scope is that

 

[fatelvis]

An old, cheap Teslong

 

[Fast14riot]

That was after cleaning the bore

If you have compressed air, shoot some down the gas tube. That looks wet still, likely just collected barrel sludge from the cleaning process.

 

[gdbleb]

If you have compressed air, shoot some down the gas tube. That looks wet still, likely just collected barrel sludge from the cleaning process.

I use brake cleaner once a year. Then run a patch down the barrel.

 

[dellet]

Wondering if you have checked it again since you probably have 4,000 rounds fired instead of 400 by now?

For the next time,
It’s not uncommon during initial brake in to be a little bullet jacket or even steel up in the port. Once you quit getting copper fouling, it’s reduced to almost nothing. It’s always good to pull your bolt apart and look at what’s stuck to the back end of it. Not a place you want to find a copper build up, but that’s where the jacket that gets shaved off the sharp edge of the port ends up and it’s worse if there happens to be a burr left behind from drilling the port.

Only concern would be alignment, it’s tough to tell from the photo, but it’s looks like at the top you can see the edge of the port in the gas block. That should never happen. The hole in the gas block is .125”, that’s larger than the port in the barrel. So you should not be able to see the block at all. Having an edge for the carbon and debris to collect on due to poor alignment may be part of the problem.

At the other end of the gas tube, it may be off enough to rub on the gas key. By now that would show. I’ve seen where they rub so bad that half the tube is worn away. Most people just bend the tube instead of confirming proper alignment at the other end.

After all that, if it is out of alignment and causing a restriction, at this point I’d probably leave it alone. You said it’s not over gassed now. If you align the port correctly, it might be. If it ain’t broke, don’t fix it.