These gas blocks are micro in size so they will fit under pretty much any rail system that a regular non-adjustable micro (or low profile) gas block will fit under. The only combination I can think of that may be an issue is using a KAC URX rail with a carbine length gas system, it may not have the proper clearance for the detent button sense the gas block sits into a pocket in the underside of the rail.

Also these gas blocks are adjustable from the front so you don't have to worry about accessing it through one of the side cut outs. The side cut outs vary in size and location depending on the rail, and different gas system lengths will also allow the gas block to land in many different locations. So having front adjustability is a huge benefit.

The adjustable block comes with two extra long Allen keys, I believe they are 6" long. One is used to press the detent and the other one is used to adjust the valve. It's a little tricky at first, and if your not careful you can slip off the detent, but it's not that bad when you get the hang of it. You definitely want to make sure that the weapon is unloaded and it's usually easier to make adjustments when the upper isn't attached to the lower. It can be done as a complete weapon but your dealing with more length, more weight, and it's a little bulkier to deal with. IMO the ONLY down side to this block is, it's not super quick to make adjustments, and if you change the valves position frequently you'll have to learn the position of the valve visually or by counting the number of turns and then always verify it's position by shooting it. Like I was saying it's not really that bad once you get the hang of it but it's not something that I would call adjustable on the fly or in the field because of it's wide range of adjustment that isn't really identifiable unless it's adjusted all the way open or all the way closed. It's not your typical adjustable gas system or adjustable gas block with an on, off, or suppressed mode. This block allows for a much finer adjustment which really allows you to dial in the operating system PERFECTLY for ANY application (caliber, ammo, buffer weight, over gassed operating system, suppressed, unsuppressed, ect..).

One complete revolution would be four detented positions.

Looks like a nice piece. Adjustable gas blocks in .625 are nearly non-existent so you are sure going to make a lot of LW Carbine people happy. Any plans on doing a .625 railed version in the future? I'd buy one in a heartbeat.

Really like the product only suggestion i would have is on the front of the detent have a small indentation that way you could use an awl or pick to push it in without the chance of it slipping off to the sides

That is a very good point. The detent DOES NOT currently recess into the gas block when it is pressed in. I have gone back and forth about the following idea. I was thinking of adding a feature that does the following. Have the detent recess into the block when it is pressed in. The Hex key would protrude into the gas block detent hole. With the current design it is not that hard to keep the Hex on the detent. I will start testing the new concept and determine if there will be an update.

Do you have any instructions for how to best adjust it? I just bought one for a 12.5" 6.8 SPC build. The barrel is mid-gas and I bought it bec. I am running it 100% suppressed.

I adjusted the GB based on ejection angle and everything seems fine, but it dawned on me later that the OPS-4 RH side charger upper does not have a brass deflector, so I'm not sure how accurate/useful the conventional wisdom about ejection angle is related to under/over gassed. I dont recall seeing any adjustment instructions, only installation instructions. I got it from Brownells.

Right now it is ejecting at about 3:30. When I started it was about 1:30.

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Mine fits under a micro sized Troy VTAC Alpha tube.

Does anyone have in tuning instructions for these? I guess the Syrac guy is AWOL from here now.

This is how I adjust my personal rifles:

The type of ammo you shoot through your rifle can and usually will make a difference on where you set the gas setting. I start by determining what ammo I am going to use to shoot through that rifle. Or you can use the lowest pressured ammo that you will shoot in the rifle. Using the lowest pressured ammo assures that the rifle will cycle with whatever you put in it. If you set it for the low pressured ammo and run high pressured ammo it might run faster than you want (more recoil). That is why I set it with specific ammo; The ammo I am going to usually shot through that rifle. The great thing about the gas block is that you can adjust it in the field to adjust to the ammo you are using.

I set it while the rifle is dry (no oil). This way when you are shooting it and it gets dirty it will have a bit more force to run. If you set it when it is wet (oiled) and it drys out or gets dirty because of high fired rounds it can slow the carrier down and cause function issues. So, I initially set it while it is dry. The gas hole in the block is totally open when the gas screw is showing three thread out of the front of the gas block. This is your starting position for the gas screw. Three threads showing.

Make sure the rifle is unloaded. Remove the magazine and visually inspect the chamber to make sure there is not a round in the chamber before you attempt to adjust the gas screw!! Remove the magazine, and visually clear the chamber every time you adjust the gas screw.



1. For the first adjustment of the gas screw, screw the screw IN three revolutions. If you need to repeat step 1, as defined in the following steps, then turn the screw IN one revolution. Make sure the screw is locked into place every time you adjust it.

2. Load the rifle with one round in the chamber and the magazine empty but locked in the mag well.

3. Fire a single shot. If the bolt locks back then screw the screw in a half a turn and repeat step 1 thru 3 until the bolt does not lock back. If you need to repeat step 1, then screw in the gas screw in ONE revolution. If the bolt did not lock back go to step 4.

4. If the bolt did not lock back then UNSCREW the screw one quarter of a turn. Load the rifle with one round in the chamber and an empty mag locked in the mag well.

5. Fire the single round. If the bolt locks back you are finished. If the bolt did not lock back then repeat 4 and 5 until the bolt locks back.

6. You can repeat steps 1 thru 5 with an oiled rifle to get the cycle rate down as low as possible.

Revised

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