Often the hardest part of keeping a pistol concealed is keeping the butt from printing or becoming exposed as the wearer moves. While one solution is to carry a compact pistol, this gives up the advantages inherent with having a longer barrel and slide.

For that reason, many experienced shooters prefer a gun with a compact frame and a full-sized slide. The traditional example is the Colt Concealed Carry Officer, which uses a 4.25-inch Commander-style barrel and slide mated with the shorter six-round Officer’s Model frame. The shorter butt makes the gun easier to conceal while retaining the accuracy potential of the Commander-length slide.

For polymer pistols, the same effect is achieved by removing material from the grip frame. This grip reduction has become an especially popular modification for the Smith & Wesson M&P line due to the lack of an “intermediate” size option between the full-sized, 17-round M&P9 and the 12-round M&P9c.

While this creates a more concealable handgun that retains the advantages of a longer barrel and slide, there are some drawbacks. The biggest is that it is a one-way trip. Once material is removed from the grip, it cannot be replaced. This process also requires one of the interchangeable palm swells to be permanently affixed, so the ability to change the grip size is also lost. This affects the pistol’s versatility and resale value.

This is where the new Hybrid kit from Cole Partnership & Training and ATEi comes in. The Hybrid kit allows the user to mount the M&P9’s 4.25-inch 9mm barrel and full-sized slide on a M&P9c frame (in place of the compact pistol’s 3.5-inch barrel and smaller slide) without permanently modifying the gun. As of now, the kit is only available for the 9mm versions of the pistol.

Behind The Kit

The Hybrid kit is the brainchild of Matthew Cole of Cole Partnership & Training in Las Vegas. “I wanted to bring a Glock-19-sized pistol to the M&P,” he said. “My goal was for something that did not require any permanent modifications to the firearm, was completely reversible and allowed the use of existing holsters.”

Cole partnered with Douglas Holloway of ATEi to bring the idea to fruition. The result is a three-piece kit covered by two U.S. patents. The kit includes a new non-captive, flat-coil recoil spring, a full-length steel guide rod and a horseshoe-shaped spacer block that fills the gap between the M&P9c frame and the full-sized slide. The kit is available in either black nitride or nickel-boron finishes. I received both versions for testing. The Hybrid kit requires an M&P9c for the host frame and a full-sized M&P9 for the donor slide and barrel.

First Steps

To install the unit, remove the barrel and captive recoil spring assembly from the full-sized slide. Slide the horseshoe-shaped spacer block onto the frame rails from the rear with the flat side facing forward (toward the muzzle) until it is fully flush against the underlug. Then reinstall the barrel, install the new non-captive recoil spring and the full-length guide rod. Now you can install the unit on the compact frame as normal. The original full-sized captive recoil spring cannot be used. It will not function properly with the spacer block installed.

I originally installed the kit with the black nitride spacer block for photos. This piece slid onto the slide and back off again easily. When I switched to the nickel-boron spacer, the extra thickness of the coating caused it to drag until it got stuck about three quarters of the way down the slide. I thought I might need a brass hammer to tap it into place but finally was able to free it enough to move it into position. A later inspection showed that some of the finish had worn off in the process.

Finishing Installation

The non-captive recoil spring was also a little tricky to install. The force required to compress the spring made it difficult to hold it in place without it kinking, binding or flying loose. Since I had to install and remove the kit several times, I got better at it, but this part of the procedure did take some time to complete. Eye protection is recommended at this point.

The field-stripping process as is normal, except on some pistols you may need to pull the slide slightly past the point where the slide stop engages before moving the takedown lever. This is due to tolerance stacking of the various parts. This wasn’t an issue on my pistol.

Once assembled, the resulting S&W can use either compact or full-sized magazines. The nose profile of the slide is close enough to stock to allow the use of holsters made for the standard full-sized M&P9. Since the compact model is used for the donor frame and no rail extensions are added, only rail accessories designed for the compact model will fit on the rail.

Hybrid Testing

I tested the nickel-boron kit at the range with a variety of target and self-defense ammunition. I carried the Hybrid with my Comp-Tac QB-1 multi-fit holster.

The Hybrid lived up to its name on the range. I first fired both my full-sized and compact M&P pistols before field-stripping
them to install the Hybrid kit. The first thing I noticed was the muzzle-heavy feel when compared to the compact gun. The extra weight up front improved my recoil management and aided in shot-to-shot recovery. Of course, the tradeoff was that the smaller frame held fewer rounds than the full-sized pistol. The longer sight radius and slightly increased velocity due to the longer barrel may also have been beneficial, but the improved recoil control was the most obvious improvement over the stock Smith & Wesson M&P9c.

For function testing, I fired about 300 rounds of mixed FMJ target ammo, including Federal’s 115-grain Hi-Shok JHPs and Speer’s 124-grain Gold Dot and 147-grain JHPs. I fired with a two-handed grip, dominant hand only and support hand only. During testing, I experienced two failures to eject, both with Winchester 115-grain FMJ ammo.

Final Thoughts

I believe the Hybrid kit for Smith & Wesson’s semi-auto M&P pistols is a high-performance part for dedicated shooters. The combo of a compact frame and a full-length slide is the best of both worlds in terms of concealability and effectiveness. The ability to switch back to the standard configuration at will makes this a no-brainer over a costly and permanent grip reduction. The ability to use any standard holsters for the full-sized M&P is a bonus.

As with any defensive pistol, the owner will have to test it to confirm functioning with their preferred self-defense ammunition. The Hybrid kit retails for $136 and is currently only available from ATEi.

For more information, visit

This article is from the January/February 2018 issue of  “Combat Handguns” magazine. To order a copy and subscribe, visit

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