Gear Review: Transforming a Glock into an SBR with KPOS

Manufactured by FAB Defense, the KPOS is a conversion kit that takes a Glock, Sig Sauer, CZ, Beretta, Jericho or FN Five-seven pistol and turns it into a short barreled rifle all in the name of personal defense.

Sold in the U.S. by Mako Group the KPOS costs less than $700. However, SBRs fall under the list of National Firearms Act items so it needs to be registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives. Tax stamp included, the total cost of the KPOS is just shy of $1,000.

I tested out the KPOS G2 system fitted for a Glock 19. Both the KPOS and Glock are part of my personal firearm stash, so what you see pictured is not what comes standard. The KPOS came to me as a basic aluminum frame, buttstock and foregrip.

Glock KPOS

Your humble author prefers a Glock carbine with a red-dot optic and flashlight. (Photo: Jacki Billings)

Transforming a Glock into an SBR

Though it’s fairly basic, the foregrip stand out most. It flips backwards and extends to fully encompass and protect the trigger area from unwanted intrusion. Perfect for families with little ones or if you carry loaded, this nifty feature adds a level of safety.

Glock KPOS

The project before assembly. (Photo: Jacki Billings)

Assembly of the full package is surprisingly quick and does not require any machining. In fact, putting it together takes only a couple of minutes.

To assemble, rotate the locking lever on the front and then pull out the rear locking pin at the but of the kit out of position. Next, lower the handguard and pull the buttstock up. Afterward, seat the Glock inside the KPOS frame.

Glock KPOS

The Glock carbine is 23.5 inches fully extended, and 14.5 inches folded. (Photo: Jacki Billings)

To secure, move the handguard back up and into place. Then rotate and secure the locking lever. Once the handguard is in place, fold buttstock back down and re-insert the rear locking pin.

Just like that a Glock transforms into a SBR and weighs in right around 3 pounds.



Is it the Glock or the KPOS that’s so much fun? (Photo: Jacki Billings)

If you’re used to the Glock experience, learning basic controls will be simple. Magazine insertion, mag release and slide release are still the same. However, there’s an added control. The kit equips the pistol with a charging handle, so no gripping and ripping.

Modeled after the AR feature, the charging handle takes two fingers to operate, but a bit more strength. I had to put some muscle behind it to get it all the way back. Smaller shooters will find it difficult but not impossible to manipulate.


Basic controls, like the trigger, still function like a Glock. (Photo: Jacki Billings)

On the range, the KPOS was no doubt exciting to shoot. I was already itching to try it out and the system didn’t disappoint in fun factor. The buttstock adds stability that in turn improves accuracy. Accurate shooting always make for a good range day. I started out at 6 yards, shooting at an 8.5-by-11-inch piece of paper. Despite freezing temperature and 30 mile per hour gusting winds, I managed a tight grouping.


Compact and easy to store. (Photo: Jacki Billings)

Challenging the KPOS and myself, I backed up to 15 yards. At 15 yards, I wasn’t as guarded from the wind. As I rocked side to side, I wasn’t so sure I would land any shots on paper.  After all, it was just a Glock in SBR clothing!

I fired six shots then approached my target to see what damage, if any, I had accomplished. At 15 yards and under blustery conditions my grouping was still quite solid. All shots were accounted for, though I had two strays that landed to the right of my group. Despite the whipping winds and my cold, shaky hands the KPOS proved to be a winner when it came to accuracy.

The KPOS is a phenomenal system — when it’s working. Unfortunately, it is prone to malfunctions and not the everyday, easy to clear stovepipes. Tap, rack and pull will not help KPOS jams.

Due to the design, spent cartridges don’t always eject properly. Instead of exiting the system, they tend to tumble around inside the kit haphazardly. Sometimes they find their way out unscathed, other times they catch the Glock’s slide while it’s seating the next round. This leads to a double feed and in some cases a horizontal double feed, where the live ammo is jammed into the spent cartridge of the previous round. A multi-tool or screwdriver must be used to pry the cartridge out and clear the firearm. This is not a quick or easy fix.

Any firearm has the ability to malfunction, but to malfunction on this level consistently is problematic. In a home defense situation there’s no time to lock the slide and dig out a multi-tool to clear the firearm. Reliability is crucial in a defense scenario and the KPOS just doesn’t measure up.

Also, a possible design flaw I saw during assembly is the locking lever on the right side of the kit.  It just so happens that I prefer my flashlight on that same side. This presents a problem as mounting the flashlight to the right covers the locking lever, preventing the Glock from being easily removed. I prefer quick access, so that left me with the conundrum of either retraining myself to use a left mounted flashlight or doing away with the flashlight completely. I chose the first. While not a deal breaker for me, it’s something to consider if a right mounted flashlight is a must have.

For your fun collection

FAB Defense’s KPOS is a novelty for sure. It’s fun to shoot and fun to own. If you like the unique, it would make an excellent addition to a NFA collection.

For less than $1,000 some kinks can be expected in a weapons system, but reliability is a big factor when it comes to personal defense weapons. For this reason, I would shy away from using the KPOS as a PDW.

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