Build of the Month

Build of the Month: Grasshopper Mouse

By Alex Fanning


Native to North America, the grasshopper mouse is not your typical rodent. Despite their small size, grasshopper mice are carnivorous and known for regularly taking on larger prey. But even more impressive is their immunity to the toxic venom of their favorite meal – scorpions.

Announced in 2009, the CZ Scorpion quickly became a popular pistol caliber carbine (PCC) for international law enforcement, and later the civilian market. So, when Swiss-based B&T introduced a new submachine gun-style PCC in 2017, the target of the GHM9, or Grasshopper Mouse 9, was clear.

Inspired by recent videos from Garand Thumb and 1911 Syndicate, we knew the GHM9 would be the perfect host for a custom build.



Like its namesake, the B&T USA GHM9 Gen2 is a lightweight and compact 9mm PCC that doesn’t compromise on firepower. Featuring a modular polymer frame with full-length receiver rail for attaching optics, lights, and other attachments, as well as ambidextrous controls and a hydraulic buffer system, the Grasshopper Mouse 9 is well-equipped to strike. Whether engaging targets on the range or maneuvering through close quarters, the GHM9 delivers exceptional handling and accuracy.

A3 Tactical Modular Folding Stock

Serving as the tail of the GHM9, an A3 Tactical Modular Folding Stock adds convenience without sacrificing stability or durability. Configurable with different adapters, extensions, buttplates, and cheek rests, ours features a strong B&T APC-specific steel hinge system that locks tight in both the folded and extended position and can be mounted to fold left or right.

Magpul MOE-K2+ Grip

The Magpul MOE-K2+ Grip combines a reinforced polymer body with comfortable, wrap-around rubber overmolding for maximum weapon control. Its steeper vertical grip angle is optimized for use on PDW and short length of pull firearms like the GHM9, and shooters can take advantage of its optional storage core for extra parts, tools, or ammo.


Swampfox Blade 1x

Like the GHM9, the Swampfox Blade 1x25mm Prism Scope is engineered for close range engagements. Particularly beneficial for shooters with astigmatism, its etched Bullet Rise Compensating (BRC) reticle was specifically designed to account for height over bore with dedicated holdovers at 5, 10, and 15 yards. Available in red, green, and amber illumination and armed with Swampfox’s Shake N’ Wake feature to conserve battery life, the Blade was our first choice to top the Grasshopper Mouse.


GSL Technology Stealth

While grasshopper mice are known for their wolf-like “howling,” this build sounds more like a squeak with a GSL Technology Stealth suppressor on the muzzle. Constructed from a blend of 17-4PH stainless steel, titanium, and aluminum, the 9mm suppressor brings superior sound suppression and recoil reduction to the GHM9. Plus, the silencer is lightweight at just 7.2 ounces and user-serviceable for easy maintenance and longevity. Prey will never hear us coming.

Weapon Light

Modlite OKW-18350

Measuring just 3.5”, the Modlite OKW-18350 provides incredible functionality and durability for a weapon light package. Combining their versatile OKW light head,18350 body, and tailcap, the light delivers an impressive 69,000 candela despite an output of only 680 lumens. Excelling in situations requiring long or wide throws, the OKW-18350 is a versatile nocturnal hunter.

Modlite ModButton Lite

Paired with the OKW-18350 is the Modlite ModButton Lite, a smaller and lighter switch providing momentary activation to the weapon light. An injection-molded plastic body and fully potted electronics provide an extra degree of protection in rough conditions while the switch is backward compatible with all Surefire, Arisaka. and Modlite Scout bodies, as well as Surefire UE and DS00 tail caps​.

Arisaka Offset Scout Mount

To mount the flashlight, the low-profile Arisaka Offset Scout Mount has never let us down. When used on the side of Picatinny rail-equipped handguards like the GHM9, the Arisaka mount places compatible lights at a 45-degree angle, allowing it to tuck in closer to the rail system. The mount is CNC machined from 7075-T651 and 6061-T651 aluminum and is MIL-A-8625 Type III hard coat anodized​ to withstand tough bumps in the night.

Why We Like It

We already liked the B&T GHM9 after a few YouTube reviews, but it wasn’t until we got one in our hands and on the range that we really fell in love with the platform.

From the first time we picked up the Grasshopper Mouse 9, its improved ergonomics and ambidextrous controls made it easy for anyone to shoot and manipulate. When Garand Thumb said it’s “the lightest recoiling blowback operated weapon” that he’s shot to date, he wasn’t kidding. Ripping rounds down range while staying on target is almost too easy, further aided by the GSL suppressor keeping muzzle rise to a minimum.

Shooting into the evening, we turned on the Modlite weapon light and had no problem seeing targets at distance with its extreme throw. And we may be biased, but the Blade was the cherry on top of this build. Even when darkness fell and with the Modlite beaming, the prism’s etched BRC reticle never lost clarity – unlike the wash out that can happen with traditional dot sights.

After our ammo had run out, packing the GHM9 was a breeze thanks to the can’s QD muzzle device and A3 folding stock. At less than 18” long, we were able to fit it inside a backpack for transport to and from the range.

Overall, the B&T GHM9 boasts big potential in a small package. Whether serving as a bedside, truck, or backpack gun, it offers a customizable platform that packs a punch above its weight.