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$2,699
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Prices accurate at time of writing
Prices accurate at time of writing
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Sig MCX Variants
- MCX Carbine: The standard MCX with a 16’’ barrel and either a semi-auto fire group for civilian usage, or a semi/full-auto group for military and law enforcement.
- MCX SBR:Short-barreled rifle variant, with 9” barrel. Available with a safe/semi-automatic trigger group for U.S. civilian sales, or safe/semi-automatic/fully automatic trigger group for law enforcement and military sales.
- MCX Pistol w/ SBX: Technically a pistol, with 9” barrel, SIG SBX stabilizing brace and safe/semi-automatic trigger group.
- MCX Low Visibility Assault Weapon (LVAW): Short-barreled, suppressed, select-fire variant available only to law enforcement agencies and militaries.
- MCX-MR (Mid Range): This one is a little bit different and is actually a semi-auto sniper rifle chambered in 7.62x51mm NATO. It comes with a 16” fluted barrel, and has both an AR-style charging handle and a SCAR-esque left-side charging handle. It uses SR-25 box mags and is compatible with SR-25 lowers. It was another submission to the military’s CSASS program, but like the LWRCi REPR, it was passed over.
- MCX Virtus: In early 2017 Sig Sauer announced an update to their MCX line of rifles renaming the series MCX Virtus. The MCX Virtus rifles have redesigned upper receivers, handguards, barrels, and bolts which are incompatible with prior MCX versions.
My Version
I was fortunate enough to be able to test out the MCX pistol with SBX brace, chambered in 5.56×45, sadly in semi-auto. The gun was brand-new in-box and had never been shot before. I loaded up some mags, wiped down and lubed up the gun according to Sig’s recommendations, and took it to the range.
First Impressions
The first thing I noticed when I picked up the gun from its shiny pelican case, was how light it is. Everywhere Sig could cut weight, they did, and you can really tell the difference even when comparing to a regular AR-15 pistol. The gun’s buffer system is entirely enclosed within the upper, so no buffer tube, which means a folding stock or SIG brace is the name of the game. Granted, a folding stock is a lot more useful on something like an SBR in my opinion but if you’re like me and have limited safe space (get it) you’ll really appreciate the option of making the already short gun even shorter. I was stuck using the SBX brace, but I still wouldn’t call the gun particularly large. In fact, running through a mock 3Gun stage with it I was struck by just how much of a difference the reduced weight and length really made. The super light pencil-profile barrel definitely helps keep the gun from being muzzle heavy. It really did feel like I was moving around with a subgun rather than something firing an intermediate cartridge. I’d say the MP5 comparisons are accurate, and the gun really does feel like a slightly grownup version of the genuinely excellent MPX. And the fact that I can basically turn it into a meaner version of an AK pistol and switch to something in a 7.62 flavor is really cool as well.
Shooting the Gun
Now, bearing in mind the short barrel, my unfamiliarity with the gun, the pistol brace for a stock, and the lack of a great trigger, I wasn’t expecting this accuracy to be super great here. Knocking plates at 25-50 yards with iron sights was a cakewalk, and every piece of paper I shot at full speed was a hit in the A zone, but stretching out to 100yds with what is technically a pistol is always cause for concern. I shouldn’t have worried. I typically default to Federal Gold Medal Match for accuracy testing because it’s one of the better factory loads I can reliably find on local store shelves, and its pretty consistent overall. With that round and slapping a Vortex Strike Eagle 1-6x (one of our favs in Best AR-15 Optics) on the MCX, I was able to get groups in the sub-MOA range no problem, with the best group coming in at about .84 MOA at 100yards. I feel like with a better trigger and a real stock, plus some better factory ammo or some nice handloads, the gun could do even better. Recoil was typically light as you’d expect for something in 5.56, and I didn’t mind shooting 300 or so rounds through the gun over the course of a few hours, even with the Sig Brace shouldered. During that time I experienced one issue with a failure to feed that turned out to be the fault of the mag (I’m rough on mags). No rifle is going to feed well from a magazine with a gnarled up feed lip, so that’s on me.
Parting Shots
The Sig MCX pistol is exactly what you’d expect to get when one of the most well-known and well-regarded firearms companies decides to make a kickass, short, light, easily-suppressed rifle.
$2,699
at Kygunco
Prices accurate at time of writing
Prices accurate at time of writing
Available Coupons
-
25% off all OAKLEY products – OAKLEY25
Copied! Visit Merchant
Ergonomics 4 / 5
Its an AR pistol. It’s not the most ergonomically designed thing out there, but it is definitely the king of the genre for me. It loses a point for that sub-par trigger, made all the more starkly irritating when you compare it to the rest of the gun.Accuracy 4 / 5
Mechanically the gun is very accurate, and I feel you could probably get down in the .5MOA range with the right ammo, the trigger drags it down a little bit here. Inside 50 yards or at “minute of bad guy” distance, you’ll be just fine.Reliability 5 / 5
It’s a Sig. It goes bang every time.Customization 6 / 5
You can take the handguards off in under 30 seconds with an Allen wrench. You can swap barrels in the field, and fire a variety of ammo out of the same gun. You can put all manner of braces and folding stocks on it. It has all the rails and keymod slots for you to mall ninja the shit out of it and ruin all that lightweight design and clean lines. Its on another level of AR-pattern customization.Looks 5 / 5
Looks are subjective, but the MCX looks sexy and if you think otherwise that’s fine. This is America and you have a God-given, constitutionally-protected right to be wrong.Price 3 / 5
“Not cheap” should be Sig’s tagline, but that price is almost always justified, and in this case I think that’s definitely true.Overall 4 / 5
Overall, the rifle (well, “pistol” in this case) meets all its design goals, but falls a little short when it comes to the trigger. That being said, you can put another bang switch in there, and even with the factory one, you’re getting an incredibly well-made, thoughtfully-designed, modular rifle. What’s not to like? Got one yourself? Let us know how you like it!
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has the rattler been reviewed yet?
WHAT CASE IS THAT?
I have the Sig Sauer MCX 300 Blackout PSB 5.5 inch barrel. I cant say anything about the others out there but this one is JUNK. It does not feed worth a damn. Does not matter if your shooting 200 + gr subsonics unsuppressed fails to feed, suppressed fails to feed, 110 gr unsuppressed fails to feed gas block on + or gas block on -. Just plain fails!!! Shouldered or held stiff armed failure. I am very dissatisfied with the grouping also not bad if your only shooting 20 yards. 50 yards it is all over the place. Pistol has a tapered barrel to threads so you will need to call and have Sig Send the tapered washer to get a true 90 degree seat so you can put your can on without risking catastrophic baffle strikes. Should of came with the purchase. They give it to you anyways so they should just include the washer in purchase.. Trigger sucks sucks sucks. Did I forget to mention this trigger sucks!!!
Wouldn't the 5.5 inch barrel be the MCX Rattler?
Not necessarily - i bought a standard MCX pistol in 556 - before they even thought up the rattler...
Then i bought a 300blk 5.5in barrel. I guess i made my own :)
Wow - sorry to hear you are having that problem! I have the SAME MCX in 300 blackout with 5.5in barrel and i have shot a few thousand rounds of all manufactures - with not a single jam, ftf of fte... i do use a silencer on it all the time... Maybe you got a lemon?
Have you tried cleaning it?