Sig MPX-K 9mm Review

If you’ve read my reviews before, you know I like to keep them short and to the point. In the spirit of that, here we go.

In a defensive situation, you don’t want to merely survive, you want to thrive. To accomplish this you need to have an edge over your opponent…the upper hand. The MPX-K was designed with this exact role in mind.

I’ve spent the better part of the past year traveling with the MPX-K in a backpack under the back seat of my truck. It rides with two full 25 round mags and a spare box of ammo. I DID NOT choose this braced pistol solely on its compact size, but this was certainly a consideration. Without trying to oversimplify things, I picked the Sig because of how quickly this gun takes a shooter to the next level when it’s needed. It short, this platform will enhance everything you may already be capable of.

The MPX-K is VERY accurate. I’ve fired a few hundred rounds from this platform and am always surprised at how intuitive it is to shoot. It groups very tight at 25-50 yards which is due to a combination of a well-made barrel, great ergonomics, and a very good trigger. It comes stock with a Timney – a trigger brand I’ve used in several long-range custom rifles.

The controls on the MPK-K will be familiar to anyone trained on an AR platform. The safety, charging handle, and mag release are right where you’re accustomed to having them…so there’s no need for building new muscle memory to become proficient with this gun.

The optic I’m using is the Sig Romeo XL which has a relatively large window to aid in target acquisition speed and everything just cooperates quickly when it’s time to get on the trigger. The brace that comes on the pistol folds to the side, and while it was more compact than the SB Tactical brace I swapped to, it did seem to rotate easily if bumped. The SB brace made the gun a little longer, but it feels sturdier when deployed.

It’s important to note that besides what you may already know about pistol braces, I actually prefer them to registering a firearm as a short barreled rifle and installing a longer stock. The reason being is that traveling across state lines with a short barreled rifle actually comes with some ATF red tape. You can do it, but you’ll need to notify the ATF with a form whereas you don’t need to with a “braced” pistol. (If you want to see the legal side of this: 18 U.S.C. § 922(a)(4); 27 CFR 478.28 )

Moving on.

The ammo I’ve been using during testing is the Sig Elite Performance 115 grain as Sig was nice enough to send a case to us. This is my first experience with Sig ammo and there have been zero ammo failures or weapon malfunctions of any kind so far.

MPX-K with SB Tactical brace fully extended.

Does Field Ethos recommend this gun?


Pros: Very accurate. Great trigger. Easy to operate. Very reliable.

Cons: Brace rotates (easy fix). Louder than hell (also an easy fix).

Upgrades: SB Tactical brace. Magpul MBUS Pro flip up sights.

Conclusion: This is a gun to buy. Everyone I’ve talked to who has one loves theirs. They come highly recommended by experts.