Bayonet Mount in front of M203? One Entrepreneurs Entry

    An entrepreneur in Seattle has developed a bayonet mounting attachment that is specifically designed for AR15s with standard front sight gas blocks. Currently, the U.S. Infantryman of today doesn’t have an option for mounting a bayonet on an M16A4/M4 that has been equipped with a 40x46mm low-velocity M203 under barrel grenade launcher (Unless he goes picatinny with Geissele). When coupled with an M4 carbine, the M203 clamps to the 6-inch barrel past the front sight post, completely preventing an issue M9 bayonet to be mounted to the carbine. A standard M203 on an M16A2 or M16A4 just barely aligns with the bayonet stud, apart of the front sight post, therefore also preventing the fitting of an M9 bayonet. However, shorter barrel M203s that haven’t been widely adopted such as LMT’s 9 inch barrel variant, or the currently issued H&K M320s would allow issue bayonets to be mounted, but it would negate the grenade launcher entirely.

    Jason Ono of NextGen Defense Research LLC’s solution is simply to replicate the bayonet stud to the 3 o’clock or 9 o’clock positions with a mount that clamps directly to the front sight post/gas block, and allows a bayonet to be mounted to the weapon while an under barrel grenade launcher is still attached and is functional. The Bayonet Adaptor as it is called is simply a bayonet stud mount that uses two screws to thread into an opposite retaining clamp that holds it together. Mounting a bayonet to the device is the exact same procedure as attaching it to the normal, 6 o’clock position, due to the birdcage flash hider allowing for this degree of offset.

    From his description of the device-

    The XM203A1 and XM203A2 side bayonet mounting system, is a technological advancement that integrates the standard Government Issue side sling adaptor, and side mounting bayonet adaptor to create a new rock solid mounting platform never before available. While originally designed for use by infantry 40mm M-203 grenadiers, this side mounting system allows the individual user to maintain a low tactical profile while the bayonet is affixed. Maximum allowances in the use of cover, concealment and defilade is thus achieved, reducing risk and exposure of the soldier to enemy fire. The side mounting system is intended for use on the M16-A2, M-4 Tactical carbine and the civilian AR-15 series of rifles. Machined to fit standard government contoured barrels. Compatibility with tactical slings or use with other tactical lights and aiming systems are not affected. A true ambidextrous design allows the unit to be mounted on either left or right of the sighting post. To be employed with or without an M-203 Grenade launcher. Knights Armament tactical rail system compatible Standard military bayonet fighting techniques such as to parry, strike and block remains the same. Combat fielding of the side mounting system in Iraq and Afghanistan has been conducted and successful. Each unit is constructed of heat treated carbon steel, Rockwell hardness of 46-48 and given a tough military parkerized finish. Testing against flesh, bone, steel and concrete have yielded positive results with no breakage to mounting system or damage to rifle.
    Model available for sale at this time is the XM203A2 which is designed to fit the civilian 16″ barrel configuration.
    DOD price for the XM203A2 is $219

    Currently producing another set of tooling for the military XM203A1 model, the standard model will be available by summer 2018 for Civilian sale.

    Bayonets are not obsolete, my device was used during the pull out of Iraq, Iraqis were not afraid of warning shots, but when bayonets were affixed, they did not advance on the line

    The product has been used in combat operations in Iraq, in the way of personal purchase or sending the product over to contacts within the U.S. Army and them experimenting with it while on deployment. The presence of ACU uniforms tells us these photographs are at least several years old.


    Infantry Marine, based in the Midwest. Specifically interested in small arms history, development, and usage within the MENA region and Central Asia. To that end, I run Silah Report, a website dedicated to analyzing small arms history and news out of MENA and Central Asia.

    Please feel free to get in touch with me about something I can add to a post, an error I’ve made, or if you just want to talk guns. I can be reached at [email protected]