Adjustable or non adjustable gas block?

[Bulletski]

Hi all:
Got a question regarding adjustable vs. non adjustable gas blocks.
I've been using adjustable gas blocks on my 2 ARs and with very good results; guns run great with them.
However, one thing that's always on my mind is if the block gets enough burned powder residue in it, then it's going to stop cycling. I try to keep the tube & block as clean as I can when I clean the guns, but my feeling is that sooner or later the block is going to get clogged enough were it won't pass enough gas through it.
Also, to do a really good job on cleaning the block & tube means having to take off the front guard, remove the flash suppressor and then disconnecting the block and then put it all back together which is not a small job.
So, that being the case, my question is: even with the advantage of one, is it really worth using an adjustable gas block?

Thanks for replies

 

[Chuck R.]

I'm a strong believer in AGBs.

I clean my 3Gun carbine about every 1000 rds or so and clean the AGB at the same time. It doesn't ever clog, just not going to happen with that much pressure passing through it. It can get seized up and not be easily adjusted due to carbon and crud though. So I use anti-seize lube grease on the moving parts.

So, yup it's an added maintenance requirement, but it is about an annual chore depending on the volume you're putting through it.

 

[CoalCrackerAl]

All my AR's run fine with the gas systems they came with. My mini 14 i did change the gas bushing. Never had to clean them out.

 

[bfoosh006]

Kroil is a great penetrating oil , I add a drop to the adjustment screw and run mine "open" and "closed" , that has worked well for my SLR Adj. GB's.

What specific brand Adj. GB are you using ?

As mentioned the pressure will keep it clear, I have never taken mine off to clean it.

Nor have I bothered to clean the gas tube.

These Adj. GB's have had thousands of rounds through them.

As for i it worth it ?
I haven't seen the need for one on my AR15 platforms, I tried a lite weight 3 Gun setup in 5.56, with a lite weight BCG and buffer setup, 18" barrel w/ a RLGS... the difference was noticable ( more a different recoil impulse ) but there wasn't enough difference to try one again on a 5.56 platform for me.

However... all my LFAR's in 308 or 6.5CM use SLR Adj. GB's , the difference is very, very noticeable in the recoil impulse on those setup's. As in Night and Day different.
I understand a lot of the difference comes down to the barrels gas port size, but out of all my LFAR barrels, with the various gas length's used and barrel lengths, only my Krieger barrel came with a appropriate ( reasonable ? ) gas port size, all the others are more generous, allowing vigorous function.

FWIW... here is a gas port pressure chart... this will help understand the PSI's generated.

 

[HKGuns]

I have zero adjustable gas blocks on my many AR platform rifles. Your needs may be different.

 

[Shawn Dodson]

I have a handful of ARs with an SLR Rifleworks adjustable gas block. After each shooting session, I do as Bfoosh006 does - I add a drop of oil to the adjustment screw and run it fully open and closed to keep it from becoming carbon locked.

If you choose to do the same, make sure you record your adjustment screw setting so you can set it to the proper setting after cycling the screw to to prevent carbon lock.

 

[CapnMac]

There are a couple arguments out there. One has been expressed above--factory is good enough. There's merit to that.
Also, if you are handloading, you likely will never need an AGB, as you are tuning to the GB you have and use. QED.

Now, if you expect to get a wide range of potentially odd-ball factory ammo, there's some logic in an AGB. Accepting, of course, that twiddling the AGB for one given box or two of ammo may not be in your best interests.

And, your specific use matters. NRA High Power and most of the run-and-gun formats, you want the AGB to get "the run" to be as consistent as possible.

Your Mileage May Vary.

 

[zeke]

On an ar-15, likely ain't required. Even suppressed. On an AR-10 style 16 in 308 i put a adj gas block on one that was already slightly over gassed so i could shoot it suppressed without it eventually self destructing. Am cleaning them with canola oil

Then there is a difference between needing one and running better with one?

 

[TonyAngel]

10 years ago, I would have advised against it as being just the introduction of another point of failure in the system.

Today? My feelings have changed. If you have a rifle you built or bought that runs right, then don't fix what ain't broke; but, if you're building a rifle or are having gas issues with a rifle you have, an adjustable gas block can make your life a lot easier.

Even here on this forum, there are threads wherein heavier or lighter buffers and/or springs are suggested to make a rifle run right. Many of the woes that shooters are looking to cure, can be addressed better with an adjustable gas block, especially considering how much Gucci springs and heavy buffers cost.

Many of the AGBs today are well made with reliable and repeatable adjustment systems.

 

[jmorris]

I only have adjustable ones on my 3gun rifles, have never clogged one, adjustable or not.

The only one I ever heard of clogging was one used too much with rimfire ammunition and never cleaned. If you start short stroking and your all the way open, you’d be #2 though.

 

[bihj]

No matter what gas block you use, if enough fouling plugs it up, the gun won't function.