Adjustable Gas Block Options

sentry1

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I'm looking to acquire a couple of adjustable gas blocks to install on my AR15 and MATEN. I like the idea of something that has a front adjusting set screw, so I can stick in an Allen wrench and make adjustments without taking the handguard off.

Having never used an adjustable block before, can anyone share some experience or specific products I can consider?
 

Rhenerie

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The Syrac adjustable gas blocks adjust from the front side of the block and are equipped with a detent system which requires you to depress it to make an adjustment. This is vastly superior to adjustable gas blocks which just use a set screw and require loc-tite to hold an adjustment. The syrac can be adjusted on the fly for different ammunition requirements. Spikes tactical also sales one, which as far as I can tell is the Syrac ordnance just rebranded.

Wilson combat also has a new one out that adjusts from the front, however it is taller than a normal low pro and uses a straight gas tube. It is how ever locking. . . so to speak. It is deeply threaded and after adjustment you can insert a second set screw to tighten against the first. An ok design and less expensive, as long as you have the extra room for height available, and don't mind removing a tiny set screw to adjust.

That's all I got. . .
 

Regalkismet

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I recommend Syrac as well.... It's sold under several names... For example spikes tactical adjustable gas block is the Syrac with the locking detent so it stays in adjustment.... Push detent in... Turn screw... Release detent to lock in.... 17 different settings. I have two...One on my 6.8 spc II and 7.62....what a difference they make.... Especially on the 7.62
 
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Dkindels

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I have the Syrac on mine as well and got it for the reasons mentioned above. Took me 5 minutes total at the range to set it where I wanted it.
 

Regalkismet

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I have to disagree..... IMHO the Syrac is a much better design. Is there a reason you think the PRI is better? I think they make many great items... Even gas blocks but I know it doesn't have a detent to lock the gas setting in place which is significant to me..... I want to know the setting doesn't change.
 
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Kiba

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Another recommendation for the Syrac. Great design-- no worries about loctite or the setscrew moving. Push in the detent, rotate to the new position, release the detent and it will stay. I've heard a few complaints about them getting carbon-clogged and difficult to move but I have yet to experience that issue.

I'd like to have them on my GAP-10 and my 2 JPs but Syrac hasn't released their .875 and .936 diameter models yet.
 

righttobeararms8

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I've got a PRI on my 3 Gun rifle and had to file a flat on the side of it so a locking nut could be installed to keep it from changing its setting during a match. I'd recommend looking into the Syrac. I've been thinking of switching over to that one myself.
 

1911nbmore

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I currently use the Syrac on my 308 AR 556 AR the design is great but I did have to machine the bottom of the gas block. It would touch the backing plate for the 6 O'clock rail segment on my Troy TRX. Seems to be common with Mid length gas systems and there 13 inch rails.
 

walnuts

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Plus one for Syrac. Works great with a can and is very easy to adjust. I have heard the adjustment screw will have carbon built
up on it after a while and becomes hard to adjust. I have be giving it a few turns every 100 rounds to keep that from happening.
 

biner626

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I currently use the Syrac on my 308 AR 556 AR the design is great but I did have to machine the bottom of the gas block. It would touch the backing plate for the 6 O'clock rail segment on my Troy TRX. Seems to be common with Mid length gas systems and there 13 inch rails.

Do you have the clamp on or the set screw model? It seems the set screw model is a little slimmer.
 

ORD

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The Syrac adjustable blocks as previously mentioned are VERY nice indeed. I have also used the Paladin Machine 3-position blocks with great success, however, unlike the Syrac and other blocks, they are not infinitely adjustable throughout a full range of adjustments.

Now as for the Syrac blocks...they can be had in both a clamp-on design, as well as a set screw design if your barrel is properly dimpled for use of the set screw blocks. The set screw model has a total height of only 1.43" (0.86" above the centerline of the bore and 0.57" below the centerline of the bore for those with somewhat "offset" handguards/rails) while the clamp model is 1.585" (0.860" above and 0.725" below).
 

LongArm

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Having had a syrac and not being able to shut the gas off and then having the adjustment screw stick from carbon. I think they suck ass. The best design is SLR's DA7
DA7 Black Rifle Gas Management System

The guys at SLR are super nice and will return calls. The owner at syrac not so much, nice but hard to get on the phone after the sale. I had to resort to posting on his face book to get him to respond. The SLR DA7 is a true one screw design with a captured detent so you don't need to hands (or three to hold the rifle). If you call SLR and tell them that you are going to run suppressed they will hand pick a gas block that is as tight as possible. You can also take the DA7 apart for cleaning which is something that will void the syrac's warranty........

If paladin had a different gas tube attachment system and more of them instock I'd have one of them too.
 

Regalkismet

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Does anyone else use the DA7? Anyone have any issues with this gas block? The Syrac has served me well.... No issues but I definitely like the idea of being able to easily clean the adjustment screw.... However I guess as long as the Syrac screw is moved every 100 rounds or so I'd probably never see an issue.... I'd imagine cheaper ammo that runs dirty probably contributes to this being an issue.. Anyone have first had experience with the Syrac screw sticking? If so how did you get it free? How many rounds before that occurred? What type of ammo? Just curious.
 

Regalkismet

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According to Syrac website it is suppose to be able to shut gas off completely.... I've never found a need to do so.... Just thought I'd mention that
 

UrbanMyth

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I have the clamp syle Syrac with a 500 round count without any problems. Easy to install. No problems with carbon fouling. It's on my duty rifle (DPMS Recon). I was able to knock some of the gas/recoil down. Yes I could tell a difference.

Hope this helps
James
 

sentry1

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Bleh, the Syrac is sold out on Brownells, where it's $85. I could get it off Amazon for $105... Buuuuut I'm cheap. I guess I'll backorder it on Brownells and just wait.
Does anyone have any experience with the Seekins adjustable gas block? I see it's in stock in a few places.
 

-Nick-

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I'm going to throw it out there... Seekin's adjustable gas block also has a set screw which does not require loctite and it's 1/2 the price. Several places also have them in-stock.
 

Crosshair

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I figured there'd be more users with the Noveske Switchblock out there, that's the one I've had my eye on for awhile. I've pretty tempted to try it out for my upcoming suppressed SBR build, though it is a little spendy.
 

WxWatcher

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Joeboboutfitters has 2 types of adjustable blocks by Kies: a set screw type for $35 and clamp-on for $44. I just bought and installed the clamp-on type. Seems like a nice piece of equipment, especially given the price. Haven't shot it yet as I'm still on the prowl for a NiB BCG....
 

Sowastrong Industries

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Haven't used it yet but I have a Seekins on my intermediate gas length Noveske. You might be able to make adjustments with the handgaurd in place but it doesn't look easy; the adjustments face the reciever. Fortunately my handgaurd comes off easily.
 

Chucky

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Syrac. The Noveske is not a fully adjustable gas block but a multi position. To customize the gas setting I would go with the Syrac.
 

ORD

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What are the .936 options?

JP Enterprises is the only one I can think of off hand (and they are not exactly "Great" in my experience with them)...Paladin may be able to make you one of their adj blocks for that large a barrel if you call and talk to them.
 

Redmanss

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JP Enterprises is the only one I can think of off hand (and they are not exactly "Great" in my experience with them)...Paladin may be able to make you one of their adj blocks for that large a barrel if you call and talk to them.
ORD, any suggestions on the JP would be appreciated as I have one for a 6.5CM barrel waiting to be assembled when I get home.
 

ORD

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ORD, any suggestions on the JP would be appreciated as I have one for a 6.5CM barrel waiting to be assembled when I get home.

The JP Blocks, in and of themselves, are just an older design that JP has done little to improve on over the years...thus, my criticism. While they have developed lower profile blocks and some different designs in recent years, they have failed utterly to address what is, in my experience, a major issue.

Essentially, they are a single-screw design with NO ability to secure the adjustment screw like so many of the current production items from Syrac, SLR, etc. which have locking detents (and other methods in some cases) to secure the adjustments once you are in the desire position. As a result, the JP adjustment screws can (and DO) work lose over time unless you modify your block or use some sort of "sealant" or loctite to secure the screw (which then kinda defeats the purpose of an ADJUSTABLE) gas block. It is just an issue to be aware of and take caution to keep an eye out for as you are cleaning/maintaining your rifle. Also, there are some threads about methods of modifying the JP blocks to install a locking screw to hold the gas adjustment screw in place. I have never done this personally (I just dropped the JP blocks in favor of others), it can be done with a little time/patience/and the right tools.
 

Redmanss

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Thanks ORD for the advice, and I did know that going in. I was planning on marking it and just keeping track, or dropping it altogether if it does end up giving me problems. It's going on a 26" Krieger 6.5CM barrel with a rifle length gas system from Fulton Armory, so I was hoping to be able to tweak the gas to run Superperformance ammunition as well. Options for a .936" are very slim.
 

scimitar2

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Not to beat a dead horse, but Syrac would be my choice. I have shot a JP until the screw walked even with Loctite on it. The retaining feature of the Syrac is worth it to me.
 

Crapshot

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Joeboboutfitters has 2 types of adjustable blocks by Kies: a set screw type for $35 and clamp-on for $44. I just bought and installed the clamp-on type. Seems like a nice piece of equipment, especially given the price. Haven't shot it yet as I'm still on the prowl for a NiB BCG....


I ordered the clamp on type as well, just couldn't beat that price.
 

Smokerroller

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I recently ordered a Noveske 16" Recon with Switchblock for a build. Once I get it all together I'll let everyone know how I like it.
 

Vette447

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What about the best option in a 0.875"?

Right now I am thinking the PRI. I would prefer to get a Syrac or DA7 as mentioned above but it appears they are lacking any 0.875" options. Too bad.

Any other good choices in 0.875" that I should be aware of?
 

Hogshooter

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I need a .875 also. I called and spoke with DA7 people and he advised that they are working on a .875 version. He advised that it should be about a month or so away from production. Design is done, he just needed to get some CNC machine time. The DA7 looks like the best option for me on a LMT MWS.
 

Vette447

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I need a .875 also. I called and spoke with DA7 people and he advised that they are working on a .875 version. He advised that it should be about a month or so away from production. Design is done, he just needed to get some CNC machine time. The DA7 looks like the best option for me on a LMT MWS.

That would be good news. I may hold out for the DA7 version then since my barrel is probably still a few months out.
 

Paulyr450

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I went with a pri because all three of my barrels are .936 but im going to look at the da7 version people are talking about.
 

Kiba

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That DA7 looks good.

While I have 2 .750 Syracs on both of my current AR15s I'm in the market for 3 more detent adjustable gas blocks for my GAP-10 and 2 JP SCR-11's; the first company to get .875 (GAP-10) and .936 (JP) diameters to market will likely get my business. Syrac says they're working on them and SLR says they are too.

Always good to have options. :)
 

Howa4AU

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PRI makes a .875 and a .936 adjustable. JP has a .936. I don't think I've seen another adjustable in .875.
 

Kiba

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PRI makes a .875 and a .936 adjustable. JP has a .936. I don't think I've seen another adjustable in .875.

I'm aware of both. My JPs have the JP adjustable gas blocks but they rely on loctite to keep the setscrew in place. I'd prefer detent-style adjustable blocks on the GAP10 and both JPs. Until Syrac or SLR releases their .875 and .936 blocks I'll stick with what's on the rifles.
 

sentry1

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I ended up going with the Seekins since it was in stock and I needed a few other items from Rainier anyway. FYI, Noveske NSR keymod accessories fit nicely on the MKM handguard. I got the QD swivel mount and the 4-piece rail section.
 

Ben Dover

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I have had seekins, syrac, and 2 different types of SLR. The SLR is the only one still on any of my rifles. Their design is superior and they have more sizes and mounting options than any of the others. The syrac was a close second but it was not as smooth adjusting and could not be taken apart.
 

Steel head

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    I have had seekins, syrac, and 2 different types of SLR. The SLR is the only one still on any of my rifles. Their design is superior and they have more sizes and mounting options than any of the others. The syrac was a close second but it was not as smooth adjusting and could not be taken apart.

    I have a SLR on my SPR build and can't imagine a gas block getting much better than that.
     

    trevoro

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    Another +1 on the Syrac even though I see you already picked one up. I've got them on both my ARs and they work great.