Description
Patent Pending
View data here. This table can serve simply to give you an idea of some potential starting points.
“Holy shit this feels like cheating.” Music to my ears.
The OMEGA Valve is the first tunable gas valve for the Sig Sauer MCX. It is made from 17-4 stainless steel via additive DMLS manufacturing, and is coated in an advanced hexagonal boron nitride coating.
It does three things:
- Instead of indexing on a ball detent within the gas block, it indexes on the gas valve retaining pin, allowing for four gas positions as opposed to the original two.
- It utilizes extended gas flow paths to delay entry of the gas into the expansion chamber of the Valve, slowing down the cycling of the rifle.
- It utilizes Parker Mountain Machine SCAR gas jet screws, allowing the user to vent excess gas out of the front of the OMEGA Valve. Also available are my own Micro Jet Screws to allow even finer tuning of your system!
When dialed in correctly, the OMEGA Valve will transform your experience with the Sig MCX. You will experience a softer recoil impulse, a less severe at-ear sound signature (when shooting with a silencer), and marginally reduced exposure to toxic gas, regardless of what ammunition and silencer you choose to use. Please note that the OMEGA Valve was designed to tune suppressed performance. Satisfactory results can be obtained in the unsuppressed state, but this was never the goal. Simply put: exceedingly under-powered ammunition may not function properly without the use of the silencer.
With your order, you will receive:
- (1) OMEGA Valve Mod. 1
- (1) Solid Set Screw (already installed)
- (1) 2.5mm wrench
This model has been tested to work with the Sig Sauer MCX Virtus, Spear LT, and Rattler LT line of 5.56 rifles. It also works to some degree in 7.62×39 barrels, but it was truly optimized for 5.56, and so it is marked “5.56.” If you are running a silencer with your 7.62×39, you should be fine.
It has been tested to work in SOME Legacy rifles, likely close to when Sig made the transition to the Virtus era. If you have a Gen. 1 (AKA “Legacy”) MCX, I would look at the “Legacy” line of OMEGA Valves. It will not work in the 5.5″ 5.56 barrel or any 300BLK rifles. See the FAQ for additional information regarding compatibility and adjustment.
Be advised: not all valves print equally, and some must be sanded and/or turned down to fit into spec and may have a more “polished” finish than others.
Disclaimer: Sig Sauer® and MCX® are trademarks of Sig Sauer, Inc. J. Bennett Designs, LLC is not affiliated with or endorsed by Sig Sauer, Inc. OMEGA Valve is an independent product compatible with the Sig Sauer® MCX® platform.
We have data available to be viewed here.

Robert Hudson –
I have been waiting for someone to innovate and create a multi-position adjustable gas valve for the MCX, and now here it is. Can confirm that it has bolt hold open on every position. Was an exceptional price considering the amount of prep and production went into the work. 5 stars
Andrew David –
Been waiting to do more testing before I wrote up anything but I can absolutely say without a doubt this valve solves any issues you may have. My 11.5 spear-lt was so overgassed that I would NEVER get a locked bolt on last round of many mags to include some Magpul, HK steel maritime, GI aluminum and a few others. Always using PMC M855. With this valve I used a 1.45 gas jet (I think, id have to double check) and now it is gassed PERFECTLY! BUY THIS!
Michael Strong –
Can’t wait to try it out, but as far as a company product looks amazing. Can’t wait to try out this a mega valve mod one and shipping was super fast.
Josh Heiliger –
Great product, great service from a really good guy/company!
Waylon Lovewin –
Works as intended. Still have some tuning to do with PMM screws (jets) to get it dialed but it is better that the stock 2 position valve for sure. 11.5 with SLX can/ M193 bulk on setting 4 is good. Soft recoil/ ejection about 2-230. Can update once further tuning is done. Would buy again. If you dont have one, stop reading this and buy one.
Dillon Scott –
Really helps with keeping the gas out of my face, especially indoor range trips
Casey –
Setting 2 with my cat WB running AAC 77otm (2700 fps version) no gas, 3 o’clock ejection.
Henry Alvarez –
Running a high back pressure can on a MCX that would always slam back, a face of gas, and shoot brass at 1 o’clock. Installed the Omega valve and now its shooting out at 3 and is definitely softer. I might get a couple gas screws to adjust slightly but just the installation of the valve made a huge difference. Thanks for a great product!
Mothman9000 –
Setting 2 100% BHO suppressed . Setting 4 100% BHO no can .
Before with factory
BHO wasn’t working 100% suppressed or non with either gas setting.
Troy –
Works as designed,spear-lt 11.5in.
77otm Griffin Armament Recce5
Position one,3 o’clock ejection
Chiefs kiss
Mike B –
Sig dropped the ball on gas adjustability on their MCX platform, the Omega valve picks up the slack. The install is straight forward and simple, and I pretty quickly was able to tune my gun for soft shooting and perfect 3 o’clock shell ejection running my suppressor.
My only heads up for buyers is if you are running a fairly restrictive suppressor, you may want to order some vent screws at the same time as you order the valve. I needed to put my solid-screwed valve in the lowest setting to achieve the results I wanted with an OVER-BORED .30 cal s-length suppressor on a 16″ 5.56 rifle. A 5.56 can of similar length and with traditional baffle designs, I’d imagine would need a vent screw to be able to get enough gas bled off for desired results. This isn’t a flaw in the valve, these guns are just really over-gassed. Definitely reference the data table Jake made up to get an idea of what you’ll need for your gun.
All in all, a great product, long overdue for the MCX platform. If I find myself owning another MCX, I’ll certainly be buying another omega valve.
Casey –
Decided to run my griffin m4sd-k on the mcx 77gr otm aac 2700fps. 3 o’clock ejection on setting 1. Training ammo .223 pmc bronze setting 2 with 2oclock ejection. I think it would benefit from a different jet for the increased back pressure of the griffin can. But it shoots soft and gas is minimal to nothing on the 77s. Outstanding upgrade
Hunter –
When I got a yhm fat cat and threw it on spear I’d get gassed out after 3 shots. After installing the omega and testing different vent screws I can now mag dump with minimum gas facial. Amazing product
Jim –
Works well in my suppressed 7.62×39 Rattler LT
Richard –
Amazing. Perfects the mcx line.
Cam –
Well worth the purchase. Highly recommend.
Jason –
Fit without issue. Reduced recoil and smoothed out the gun as described. Great job!
Damon Webb –
Well done!!
Chaz Turbino –
On a 11.5″ 5.56 Spear LT with the solid jet, Setting 4 felt about as aggressive as the factory regulator on the “-” setting, ejecting at 3:00. I couldn’t get any of the commercial ammo to run on Setting 3 unsuppressed (Federal AE 223 55gr FMJ, IMI M193, Norma SS109/M855, or IMI 77gr Razor Core) which was surprising as the data table on Jake’s site showed a few people able to run on setting 3 with the solid screw. With a flow can suppressor (Specifically the SIG SLX556-QD/NG556-QD and the NGSW suppressor aka SLX-MG/NG68SPEAR-QD) it ran on Setting 3 without any issues and was ejecting at about 3:00 (versus 1:00 with the factory regulator). My next plan is to try different gas jets to tame the unsuppressed config in setting 4 and to see if it will still work suppressed in setting 3.
Erik Berthoty –
fixed my supresson issue. Position 4 is a bit gassy though
Eddie Keomoungkhoun –
I finally got around to running a couple of different rounds through the Mcx spear LT 11.5†7.65×39 suppressed with the SilencerCo Omega 300. Here are my results:
Hornady Black 7.62×39 123gr SST at 100 yards on gas setting 3, full lock back and successful feed. 5 groups at .89†MOA, Also the cleanest burning round I’ve had to date.
Norma R&T 7.62×39 123gr FMJ at 100 yards on gas setting 3, full lock back and successful feed. 5 groups at 1.01†MOA.
Conclusion, this one little upgrade made me love the Mcx spear lt rather than before I didn’t want to pull it out of the safe anymore. Runs flawlessly and I can finally say if it was my only rifle I’d trust it with my life.
Lukas Gephart –
Product is of outstanding quality and works as advertised. Makes the Spear LT a much more desirable platform and in my opinion, a superior suppressor host to a DI AR-15. Jake is also a stand up guy, he deserves your trust and support.
Thomas Duff –
Was running a 556 Polonium with an 11.5 Spear LT. was extremely punchy and overgassed to all hell. Threw the omega valve in there and it runs like a dream.
Setting 4 is perfect for Lake City M855 and M193. Setting 3 is great for the downloaded 55gr offerings that are so common today from companies like PMC and Fiocchi.
Adjustments are quick so you can make anything work. Thanks so much for making a great product!
Shandon Prater –
I wanted a sig mcx spear Lt for a long time and I finally bought one, I was immediately was disappointed. It was crazy gassy and recoiled bad. This single piece changed everything!!! Love it!!!
Adam Howard –
So far it has performed great. It has lowered the recoil impulse and even increased the reliability of the FRT installed. If I had to do it all over again I would definitely would buy again and bought it sooner. For context I am running a 11.5″ 5.56