What do you believe the best home defense firearm to have is?

A pistol?  A rifle?  A shotgun?

If you had to respond to a loud crash downstairs, which type of gun would you bring?

Many people would likely answer with a shotgun, and with good reason.  It’s reliable and it’s devastating in close quarters.  Other people would likely answer with a semi-automatic rifle like the AR-15.  Yet others would say a pistol or revolver, which is much more wieldy in narrow spaces.

But what about a pistol caliber sub-machine gun sized gun instead?  No, not a true sub-machine gun, but just a semi-automatic pistol that’s roughly equivalent in size to a submachine gun like the H&K MP5 or the Uzi.  How would that work for home defense?

It turns out that SIG Sauer has an answer to that question with a relatively recent gun of their own.

Shorty #sigmpx #mpxk #subgun #mp5 #9mm #mro #inforce #redtape #sbtactical

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The specific make and model of gun that is being referred to here is the SIG Sauer MPX.  At first glance, it certainly looks like a submachine gun, but in reality it’s just a semi-automatic pistol with the magazine located in the front of the trigger guard.

Sig Sauer MPX
Sig Sauer MPX Variants


This gun was made by SIG Sauer with the intended purpose of being used for self-defense and home defense.  It’s a shorter gun than a shotgun, rifle, or even a carbine, and yet it has a much  greater magazine capacity than any traditional pistols like a Glock 17 or Beretta 92FS.  The MPX is also heavier than a traditional pistol, which helps make it more controllable to tame recoil.

The MPX also comes installed with a Picatinny rail across the top of the firearm for you to add a red dot or a laser of some kind.  The quick detachment sling mount on the gun also enables you to carry it with a single point sling.

MPX Picatinny rail with Keymod Handguard

The MPX also uses a short stroke piston system, in contrast to the blowback or direct impingement systems that are more popular.  The advantage to using a short stroke piston system  is it helps keep the gun cleaner after extended firing sessions, which also in turn helps with reliability.

The controls of the MPX, as you will notice when you first pick it up, are incredibly similar to the AR-15.  This is good for training purposes because using the MPX effectively won’t be that much different from an AR-15.  Nonetheless, the MPX is not an AR that has been scaled down to accept the 9mm round.  There’s still a learning curve to it as it is its own unique platform.


One specific variant of the SIG Sauer MPX is the MPX PSB (which stands for pistol stabilizing brace).  This is designed to help make the MPX a pistol caliber short barreled rifle in a sort of way.

Sig Sauer MPX

The SIG Arm Brace that the MPX PSB ships with the gun.  The braced is secured to a folding hinge, which in turn is attached to the MPX via a picatinny rail located at the rear of the receiver.  Shooting the MPX PSB when you have the arm braced velcroed over your arm means that there is very little movement in the stock, which translates to easier firing and better controllability.

One negative point about the MPX PSB is that it does not ship with iron sights, but this is something that you can remedy on your own (with added costs, of course), because SIG Sauer makes iron signs that are designed specifically for the weapon.


Make: SIG Sauer

Model: MPX PSB

Caliber: 9mm Luger

Capacity: 30+1

Barrel Length: 8 Inches

Overall Length: 16.7 to 24 inches depending on the position of the stock

Overall Weight: 6.1 pounds


One more thing that should be mentioned about the MPX in general is that it is not an inexpensive weapon.  An MPX is going to run you two grand at least, and probably several hundred dollars more depending on where you find it.

But still, there’s no denying that the MPX would serve as a very effective home defense weapon.  This is a compact firearm, easy to maneuver in tight conditions such as your house, and with a large capacity and easy controllability, more so than many other pistols or even some rifles.

In that regard, it may be worth the extra price tag to you.

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