Which adjustable gas block for my LaRue Grendel?

[LittleLebowski]

The barrel is a .750, pics of existing gas block attached.

https://www.brownells.com/search/index.htm?k=adjustable%20gas%20block

48365

[texasaggie2005]

Good luck getting that block off. Mine was on tighter than a BCM.

[LittleLebowski]

Good luck getting that block off. Mine was on tighter than a BCM.

Great. I had to cut off my last BCM gas block.

[awp_101]

Why are you looking to go to an adjustable? Because suppressor or another reason? If it’s for suppressor use, any chance Larue might have a recommendation?

[Clusterfrack]

I have yet to need an adjustable gas block on any of my gas guns, including my 6.5 Grendel. I shoot them suppressed and unsuppressed, and all I've needed to do was use the right weight buffer.

I have seen a bunch of adjustable gas systems go TU at inconvenient times. Especially JP stuff.

[HCM]

I have yet to need an adjustable gas block on any of my gas guns, including my 6.5 Grendel. I shoot them suppressed and unsuppressed, and all I've needed to do was use the right weight buffer.

I have seen a bunch of adjustable gas systems go TU at inconvenient times. Especially JP stuff.

This.

If for some reason you could not find the proper spring and buffer combo, I would look at one of the adjustable ball carriers from Jim tech or bootleg before I would mess with an adjustable gas block.

Are you having functional issues or are you simply trying to reduce the back pressure?

Back pressure is definitely a thing with DI ARs. La Roux only guarantees their guns and uppers to work with their cans and sure fire cans due to back pressure issues. Usually the quieter the can the more back pressure.

[LittleLebowski]

I’m trying to reduce gas to the face. This is a precision gun, I’m not too worried about high round counts gumming up the AGB.

[Dan_S]

I’m trying to reduce gas to the face. This is a precision gun, I’m not too worried about high round counts gumming up the AGB.

I think we’ve talked about this before here, but if not....


http://www.blackrivertactical.com/

Look at the gas tubes, and/or the microtune has block.

[jbrimlow]

Adjustable gas blocks: try SLR? They have a ton of sizes, and they seem better made than a lot of the others.

I've also heard good things about the Superlative Arms venting gas blocks.

[jbrimlow]

Also, if you oil them and work them through the range of adjustments after use, that usually gets them to avoid locking up.

[dfeder530]

I have a Superlative Arms gas block on an 11.5" DI AR that I use exclusively suppressed with a Dead Air Sandman K silencer. It's not used for anything other than the range and occasional 2-gun competition, but it works really well to reduce gas to the face and tune recoil down to a minimum with a standard spring and carbine buffer. I've gone with the understanding that the "adjustable" part of the gas block is supposed to be tuned and to leave it, rather than something that's constantly messed with after each range trip. That being said, I have shot hundreds of rounds then messed with the detent adjuster and it clicks just fine and reliably returns to the gas setting I configured it to originally. Using steel cased .223 Tula or Wolf I get 4-5 o'clock ejection patterns and with .223 Wolf Gold I get 2-3 o'clock ejection.

[HCM]

I’m trying to reduce gas to the face. This is a precision gun, I’m not too worried about high round counts gumming up the AGB.

The real answer to GTF is lower back pressure cans.

The other issue with AGB, is leakage.

[LittleLebowski]

The real answer to GTF is lower back pressure cans.

The other issue with AGB, is leakage.

I think it's a little cheaper to buy an AGB than a new can, just saying :D

[whomever]

Apologies for the tangent - I haven't been following your build, but have you looked at the vented charging handles like:

https://www.griffinarmament.com/sn-ach-suppressor-normalized-ambi-configurable-handle/

Being a cheapskate, I just took a plain jane charging handle and drilled a hole like you see at the right rear of that one and used a squirt of RTV to do the DIY gasbuster thing. It would probably get you kilt on the streetz, but it fixed my problem for $0 and a few minutes work.


googling to find the pic turned up other variations:
https://www.primaryarms.com/radian-raptor-sd-ambidextrous-vented-ar-15-charging-handle-black
https://www.weaponoutfitters.com/ar-gas-vent.html
those would have cost money, though :-)

[Crews]

I had one of those, also in a precision-oriented use case. Pretty sure I ended up drilling one of the set screws out to get the gas block off. Put on an SLR, nothing but positive results. It’s a standard operating procedure for me with a suppressor.

Also, sorry for the extra thousand and I know the purists will despise me...... but a JP H2 SCS and LMOS BCG in conjunction with tuning the gas block took my Larue to a whole different dimension. Much more enjoyable to shoot, and I noted some improvements in the rifle’s performance at the range.


Sent from my iPhone using Tapatalk

[jbrimlow]

I had one of those, also in a precision-oriented use case. Pretty sure I ended up drilling one of the set screws out to get the gas block off. Put on an SLR, nothing but positive results. It’s a standard operating procedure for me with a suppressor.

Also, sorry for the extra thousand and I know the purists will despise me...... but a JP H2 SCS and LMOS BCG in conjunction with tuning the gas block took my Larue to a whole different dimension. Much more enjoyable to shoot, and I noted some improvements in the rifle’s performance at the range.


Sent from my iPhone using Tapatalk

+1 on the low mass operating system and SCS. It shoots so nice.

[DpdG]

I do not have a large round count through it yet, but so far I have been very pleased with the Superlative Arms bleed off block. As I understand it, one of the benefits of the bleed off versus deadhead style adjustment is that it is much less prone to the adjustment mechanism becoming carbon’d up. The gas flow through the block venting to atmosphere should prevent it from becoming frozen, while also reducing gas blowback down the barrel.

With all that said, if staying with one configuration (suppressed or un-suppressed) I would much prefer a fixed block with a properly ported barrel over even the best adjustable block.