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Ultimate gas block of choice | update on riflespeed

Bilb0

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Sep 16, 2023
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Dexter, Missouri
What is the ultimate gas block for durability, longevity etc. Will not be running suppressed on this rifle anytime soon but possibly in the future. I know these parts below will be a determining factor as well:

  • 223 wlyde Criterion core 18" with rifle length gas system. .625
  • LMT Enhanced BCG
  • I believe I've read the A5 buffer system would be ideal (not sure specifics on buffer weight yet.)

You input would be appreciated so I get it right the first time. I've read for days on end; on most mentioning superlative adj gas block or SLR,

I wanted thoughts on non adjustable as well, I was wondering if anyone had any experience on the PRI flip up front sight with .625 crossbolt. Or if that's silly.

I know the EBCG will come into play so I was interested in your expertise.


Thanks ahead of time
 
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Riflespeed gas block. I’ve had both Superlative and SLR and have not had any issues with them, but I hate having to keep a small specific tool around to adjust them. I’ve converted three of mine to Riflespeed and I’m not looking back. They are infinitely adjustable because of all the different plungers they sell; I have yet to need any plunger other than what they send with the units at purchase and I’m running them on 223 carbine length, 308 mid length, and 6.5 cm rifle length. .625 boss is no issue and not a limit for any decent AGB sold these days.

 
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The .625 shoulder dimension limits what is available. I have never used Riflespeed, so cannot comment on it. Superlative adj gas block and SLR are good from my experience.
 
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Riflespeed gas block. I’ve had both Superlative and SLR and have not had any issues with them, but I hate having to keep a small specific tool around to adjust them. I’ve converted three of mine to Riflespeed and I’m not looking back. They are infinitely adjustable because of all the different plungers they sell; I have yet to need any plunger other than what they send with the units at purchase and I’m running them on 223 carbine length, 308 mid length, and 6.5 cm rifle length. .625 boss is no issue and not a limit for any decent AGB sold these days.

Okay cool so you've been through the lot. I was checking riflespeed out the other week, thank you for reminding me. I DEFINITELY do not care for the typical adjustable gas block bolt/screw head and tool.
 
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I use Superlatives. I normally shoot suppressed and don’t find myself needing to adjust the block after the initial setting unless I’m switching between heavy and light bullets. In one rifle I keep the supplied Allen key retained to the gun with a ranger band.
 
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I use Superlatives. I normally shoot suppressed and don’t find myself needing to adjust the block after the initial setting unless I’m switching between heavy and light bullets. In one rifle I keep the supplied Allen key retained to the gun with a ranger band.
Okay great! Thank you for your response. So you only adjust depending on the bullet weight.

What about if you choose to run unsuppressed, do you have much adjustment from your initial setting?

What have you done if you get distracted and lose track of how many clicks mid turn 🙂
 
Okay great! Thank you for your response. So you only adjust depending on the bullet weight.

What about if you choose to run unsuppressed, do you have much adjustment from your initial setting?

What have you done if you get distracted and lose track of how many clicks mid turn 🙂
I set my guns to shoot well suppressed and they tend to still cycle, but a little slow, when I suppressed. Somehow all of my guns end up at ~14 clicks (3.5 turns) from fully closed so it’s very easy to remember. Just crank to zero and back out 14.
 
I know these parts below will be a determining factor as well:

  • 223 wlyde Criterion core 18" with rifle length gas system. .625
  • LMT Enhanced BCG
  • I believe I've read the A5 buffer system would be ideal (not sure specifics on buffer weight yet.)
I know the EBCG will come into play so I was interested in your expertise
It's a gas block. As long as it's doing its job, none of this stuff is relevant.
There is no "ultimate".
 
I set my guns to shoot well suppressed and they tend to still cycle, but a little slow, when I suppressed. Somehow all of my guns end up at ~14 clicks (3.5 turns) from fully closed so it’s very easy to remember. Just crank to zero and back out 14.
I gotcha, that's easy enough just returning to zero then back to the # of clicks you found suits best
 
It’s a gas block. One of the few areas where there really isn’t any benefit to upgrading from mil-spec for anything other than creature comfort.

I can agree in regards to an unsupressed AR15 in 5.56, an AGB is not actually a “need”. Once you go suppressed or get into AR10 platforms I strongly disagree.

In my experience with AR15’s in 5.56 with AGB’s going back and forth with and without suppressors, you can have two settings that will work with just about any ammo you try to run. In my AR10 platform’s with titanium bolts and low mass buffers, I have to tune more frequently and have slightly different settings for different ammo, which makes the Riflespeed AGB a welcomed addition over a tool adjusted SLR or Superlative.

Depends on your application, for me, being able to adjust without a tool trumps all else.
 
FWIW... I tend to set the SLR Adj. GB to 100% function, and then open it another click or 2. Mine are on LFAR's, various barrel lengths and gas system lengths in 308 and 6.5CM. They all tended to work, as I desire, opened 6'ish clicks of the available 15.
And FWIW... all my LFAR's have Adj. GB's.

I never really fuss with them after that. Except to put some Kroil through the screw in the block threads.

In other words, I don't re-tune for every load.

I have none of the LFAR's suppressed... so YMMV.

The 1 SLR Adj. GB I tried on a 18" FN CHF CL 5.56 RLGS , really didn't do much that I could tell. ( go figure, right ? )
It is set up for 3G.. low mass cycling , etc

I would try your barrel first, with a normal GB.
 
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Ultimate durability would be one built into the barrel, i.e.no actual gas block at all. HM Defense does one, and I have one of their barrels on my “TEOTWAWKI” build upper:

IMG_5808.jpeg


However, it sounds like you already have a pencil profile barrel, and need a .625 gas block. Is this correct?

For that, I’d lean towards titanium vs steel simply because you get a tighter fit as the barrel heats up. V7 does a nice pinned gas block (I have several), and they do one for .625 barrels: https://www.vsevenweaponsystems.com/upper-parts/v7-pin-on-titanium-gas-blocks


fullsizeoutput_81d.jpeg


If you’re just looking for a good, lightweight option, my favorite is the 2A Arms; it’s non-adjustable though. Edit: and they’re no longer available now that NEMO bought them out…. Bummer. There was also a company called ‘Master of Arms’ that did an awesome adjustable gas block too, but it looks like they’re no longer in business either. Edit: Wing Tactical appears to still have them in stock, but none in .625

Bottom line: I have barrels with clamp on gas blocks that I’ve put thousands of rounds through with zero issues, but for ultimate reliability/durability you really should consider a pinned gas block; adjustable or not.
 
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I can agree in regards to an unsupressed AR15 in 5.56, an AGB is not actually a “need”. Once you go suppressed or get into AR10 platforms I strongly disagree.

In my experience with AR15’s in 5.56 with AGB’s going back and forth with and without suppressors, you can have two settings that will work with just about any ammo you try to run. In my AR10 platform’s with titanium bolts and low mass buffers, I have to tune more frequently and have slightly different settings for different ammo, which makes the Riflespeed AGB a welcomed addition over a tool adjusted SLR or Superlative.

Depends on your application, for me, being able to adjust without a tool trumps all else.
Yeah I just checked out the riflespeed more last night
FWIW... I tend to set the SLR Adj. GB to 100% function, and then open it another click or 2. Mine are on LFAR's, various barrel lengths and gas system lengths in 308 and 6.5CM. They all tended to work, as I desire, opened 6'ish clicks of the available 15.
And FWIW... all my LFAR's have Adj. GB's.

I never really fuss with them after that. Except to put some Kroil through the screw in the block threads.

In other words, I don't re-tune for every load.

I have none of the LFAR's suppressed... so YMMV.

The 1 SLR Adj. GB I tried on a 18" FN CHF CL 5.56 RLGS , really didn't do much that I could tell. ( go figure, right ? )
It is set up for 3G.. low mass cycling , etc

I would try your barrel first, with a normal GB.

I may try out this A.R.M.S #41 flip up gas block from a guy I'm negotiating until I decide which AGB I would go with if I decide to run suppressed. Anyone have any/heard any experience with A.R.M.S?

Let's just hope its the .625 he says and not a .75 haha


20240201_161816.jpg


20240201_173036.jpg


41-B-L-2__25133.jpg
 
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Ultimate durability would be one built into the barrel, i.e.no actual gas block at all. HM Defense does one, and I have one of their barrels on my “TEOTWAWKI” build upper:

View attachment 8337374

However, it sounds like you already have a pencil profile barrel, and need a .625 gas block. Is this correct?

For that, I’d lean towards titanium vs steel simply because you get a tighter fit as the barrel heats up. V7 does a nice pinned gas block (I have several), and they do one for .625 barrels: https://www.vsevenweaponsystems.com/upper-parts/v7-pin-on-titanium-gas-blocks


fullsizeoutput_81d.jpeg


If you’re just looking for a good, lightweight option, my favorite is the 2A Arms; it’s non-adjustable though. Edit: and they’re no longer available now that NEMO bought them out…. Bummer. There was also a company called ‘Master of Arms’ that did an awesome adjustable gas block too, but it looks like they’re no longer in business either. Edit: Wing Tactical appears to still have them in stock, but none in .625

Bottom line: I have barrels with clamp on gas blocks that I’ve put thousands of rounds through with zero issues, but for ultimate reliability/durability you really should consider a pinned gas block; adjustable or not.

Yes .625; Awesome, this is some great info I haven't came across before. Didn't know they had barrels with gas blocks built in lol, nor that titanium expands at a higher temp than steel. That would make logical sense on titanium over steel. I've pinned plenty that wouldn't be a problem.

I'll look into what you've mentioned. Thanks for the Info. 👊
 
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I have a VLTOR clamp on gas block with the built-in front site, and a qd attachment point on one of the first builds I did when we moved back to the US back in ’12…it’s still going strong. And it gets worked hard at least once every other weekend as a training rifle for our extended friends/family support network:

i-Wcdxpxf.jpg


That BCM barrel has to be getting close to being shot out by now. Bottom line: Clamp-on is generally just fine if you do it right, but I’m a belt and suspenders kind of guy when it comes to this kind of thing…pin on (or built in) all day long for me.
 
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I have a VLTOR clamp on gas block with the built-in front site, and a qd attachment point on one of the first builds I did when we moved back to the US back in ’12…it’s still going strong. And it gets worked hard at least once every other weekend as a training rifle for our extended friends/family support network:

i-Wcdxpxf.jpg


That BCM barrel has to be getting close to being shot out by now. Bottom line: Clamp-on is generally just fine if you do it right, but I’m a belt and suspenders kind of guy when it comes to this kind of thing…pin on (or built in) all day long for me.
That's great to know its still going strong. Ill enjoy overengineering this chained suspenders chastity belt system 😁
 
You try a $30 STD .625 gas block first. If it's undergassed, you drill your gas port large by .002" with a Harbor Freight numbered drill bit kit. You are looking for 3 O'clock ejection. This 3:30-4:00 is for dirtied up guns. You don't want to start with ejection at 3:30-4:00.
 
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Huh... I didn't realize those A.R.M.S flip up even came in .625 diameter. Learned something new today.

The one I saw needs to be pinned... "Pinned (must be installed by gunsmith)"

Yeah that's the one #41 B-L-P. I found a guy who has one but he said he "thinks" it's a .625.

I looked up his specific stag arms 16" 1/9 twist Chrome-Moly Vanadium barrel and all I've found is .75

I'd have to buy his barrel and gas block together, he won't split it and he's wanting $460 for the pair.

He quoted:

"I spent over $200 on the barrel buying it new and having it profiled like the 1/7 barrels and pinning and welding the flash hider."

"ARMS #41 SILHOUETTE™ Front Folding Sight Taper Pinned by TNTE to a Stag ARMS chrome lined 1/9 Twist Barrel. The barrel was original 16" but was cut down to 14.75" crowned and threaded then a Extended flash hider was pinned for 16" Legal min barrel length".

That would be an expensive mistake for me to make if it's not .625 journal.

Screenshot_20240202_035028_Brave.jpg
 
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So the guy spent big money getting a barrel machined but has no idea of the specs? Sounds real bright.
Pic looks like .75 FWIW. Don't buy it till he sends a pic of calipers on it just ahead of the block at least. If he can't do that, hard pass.
 
"I spent over $200 on the barrel buying it new and having it profiled like the 1/7 barrels and pinning and welding the flash hider."

"ARMS #41 SILHOUETTE™ Front Folding Sight Taper Pinned by TNTE to a Stag ARMS chrome lined 1/9 Twist Barrel. The barrel was original 16" but was cut down to 14.75" crowned and threaded then a Extended flash hider was pinned for 16" Legal min barrel length".

Who cares if that barrel is .75 or .625; $460 for a 1 in 9 twist Stag barrel is a VERY hard NO! You can get a barrel that’s infinitely better for that kind of money. Thats not a purchase anyone should consider.


 
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Yeah that's the one #41 B-L-P. I found a guy who has one but he said he "thinks" it's a .625.

I looked up his specific stag arms 16" 1/9 twist Chrome-Moly Vanadium barrel and all I've found is .75

I'd have to buy his barrel and gas block together, he won't split it and he's wanting $460 for the pair.

He quoted:

"I spent over $200 on the barrel buying it new and having it profiled like the 1/7 barrels and pinning and welding the flash hider."

"ARMS #41 SILHOUETTE™ Front Folding Sight Taper Pinned by TNTE to a Stag ARMS chrome lined 1/9 Twist Barrel. The barrel was original 16" but was cut down to 14.75" crowned and threaded then a Extended flash hider was pinned for 16" Legal min barrel length".

That would be an expensive mistake for me to make if it's not .625 journal.

View attachment 8338933
The folding FSB shown in the post I quoted has been pinned. Even if it is the right diameter, removing it to reuse on another barrel would be very difficult, if that is your intention.
 
So the guy spent big money getting a barrel machined but has no idea of the specs? Sounds real bright.
Pic looks like .75 FWIW. Don't buy it till he sends a pic of calipers on it just ahead of the block at least. If he can't do that, hard pass.
Agreed ! that's what my brain concluded as well😁
 
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I have a .625 PRI crossbolt sight. I'm not sure what you mean by experience. They work like any other flip-up.
I love PRI stuff, just not the price.
 
The folding FSB shown in the post I quoted has been pinned. Even if it is the right diameter, removing it to reuse on another barrel would be very difficult, if that is your intention.
His is .75, had him measure it; so that's a no go. I have a machine shop handy. Prob get a fixed or adjustable to play with until an ARMS #41 pinn-able graces my presence.

Might as well make it look sharp since it's an exposed gas block. Too many goodies to choose from I feel like an ADHD kid in a candy store trying to decide shesh. I need to be won over. Why of all parts is this one so much more difficult to choose lol
 
I have a .625 PRI crossbolt sight. I'm not sure what you mean by experience. They work like any other flip-up.
I love PRI stuff, just not the price.

Experience as in someone who has owned one and have had it in their presence, maybe had short conversations with it when alone. Made it get hot, get your money's worth; show who owns it etc.
 

This is the “Ultimate” gas block for your build. It’s built specifically for the Criterion CORE series barrels. With 18”/rifle gas and the correct suppressor, you shouldn’t need an adjustable gas block.
 
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This is the “Ultimate” gas block for your build. It’s built specifically for the Criterion CORE series barrels. With 18”/rifle gas and the correct suppressor, you shouldn’t need an adjustable gas block.
I have an 18” CORE that I can shoot suppressed and unsurpressed with minimal change in ejection patten with a MWI fixed gas block.

FYI, the CORE profile makes for a handy rifle, but it does have a noticeable POI shift with adding a suppressor. I ultimately ended up taking mine off because I hated the handling of it for positional shooting.
 
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This is the “Ultimate” gas block for your build. It’s built specifically for the Criterion CORE series barrels. With 18”/rifle gas and the correct suppressor, you shouldn’t need an adjustable gas block.

Yeah I was checking out this gas block after I heard criterion mention this in a video about ripcord
 
I noticed this today looking at a.r.m.s.front sights; I assume this is a railed gas block with a switch on it?

3 (1).jpg
 
I have a pretty similar build to yours, core barrel, Lantac enhanced bcg (not LMT obviously), superlative arms gas block.

To answer your buffer question, vltor H2 runs fine. It was the "standard" buffer they supplied with the full kit, before they started selling the weights separately.

https://www.arbuildjunkie.com/vltor-a5-buffer-system-overview/ this covers their different weights used and application pretty well, its an interview.
 
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I have a pretty similar build to yours, core barrel, Lantac enhanced bcg (not LMT obviously), superlative arms gas block.

To answer your buffer question, vltor H2 runs fine. It was the "standard" buffer they supplied with the full kit, before they started selling the weights separately.

https://www.arbuildjunkie.com/vltor-a5-buffer-system-overview/ this covers their different weights used and application pretty well, its an interview.

Excellent! 👍 Thank you for sharing that; I was curious what standard buffer came with their full kit and which would be a better fit h2 or h3.
 
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I love the Riflespeed if it works for your application…

View attachment 8342421

Im trying to understand their "fitment" chart myself. Tool-less adjustment is appealing, especially once you add in a muzzle device or anything else that makes it more difficult to snake in an allen wrench.

I used the configurator and got the no/red for all of my measurements, but if the last 2 digits in the model are "overall length" of the block and control, then a RS7533 could work for me, with a little over an inch of barrel exposed.

I contacted them a few days ago, but never heard back, so have been delaying ordering one to try for that reason.
 
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my personal take:

1) unsuppressed, standard 20" rifle barrel or 14.5" carbine: ARMS #41BL all day
2) Suppressed and unsuppressed barrels of various lengths, various calibers: Superlative Bleed-off adjustable
3) unsuppressed but tuning for minimal felt recoil or maximum reliability for specific loads: Riflespeed.
 
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my personal take:

1) unsuppressed, standard 20" rifle barrel or 14.5" carbine: ARMS #41BL all day
2) Suppressed and unsuppressed barrels of various lengths, various calibers: Superlative Bleed-off adjustable
3) unsuppressed but tuning for minimal felt recoil or maximum reliability for specific loads: Riflespeed.
If I go adjustable I'll prob go tool-less like riflespeed as you mentioned. And if I go fixed then the flip up style gas block if I could even find an A.R.MS #41BL
 
If I go adjustable I'll prob go tool-less like riflespeed as you mentioned. And if I go fixed then the flip up style gas block if I could even find an A.R.MS #41BL
The main reason I like the superlative bleed-off for suppressed is that once you set it you very rarely have any cause to fiddle with it, since any extra gas from suppressor blowback just gets vented
 
The main reason I like the superlative bleed-off for suppressed is that once you set it you very rarely have any cause to fiddle with it, since any extra gas from suppressor blowback just gets vented

But what if I won't be running suppressed initially. But a gas block that can be dialed in depending on the ammo used, and then down the road dialed in for suppressed as well.