This week another image of a very rarely seen shotgun in Ukraine appeared, an M26 Modular Accessory Shotgun System. These are magazine-fed, bolt-action shotguns which can be mounted on rifles.
The M26 is essentially the US military’s bolt-action Masterkey at home. Developed in the early 2000s by C-More Systems it was selected by the US Army in 2008 and began fielding in 2011 seeing operational service in Iraq and Afghanistan. It is still in service today.
The shotgun has a 3 inch chamber and uses a straight-pull bolt-action. It’s box magazine-fed with 3 or 5 round capacities available. It can also be used as a standalone once a stock and pistol grip assembly is attached, it has folding back-up iron sights but uses the rifle’s sights when mounted. The MASS’ safety and bolt-handle are reversible to allow ambidextrous operation. The M26 was designed to be employed as a breaching shotgun for shooting hinges and locks, the barrel is tipped with a breaching stand-off adapter muzzle-device. In its rifle-mounted configuration the M26 weighs around 3lbs (1.4kg) and has an overall length of 16.5 inches (42cm). It has an improved cylinder bore profile (sometimes referred to as a 1/4 choke), meaning it has an integral choke with a slight constriction that allows the shot to spread quickly after leaving the muzzle, the practical range for this type of choke is around 15-30 yards.
The most recent sighting of one of the shotguns came on 19 December. Ukrainian outlet Tysk shared a photograph of a Ukrainian operator armed with an M4A1 carbine topped with an ACOG and equipped with a M26 MASS In Ukraine. The M26 in the photograph appears to be loaded with a five-round magazine.
Sightings of the M26 in Ukraine are extremely rare, with the only other example appearing in a ХЛОПЦІ З ЛІСУ (Boys from the Forrest) video which showcased weapons used by the UA Reg is the 1st Special Operations Detachment of the 8th Regiment, SSO (UA SOF). The M26 seen in that video was in the standalone configuration with pistol grip and stock attached. Sadly, the shotgun itself wasn’t discussed in the video.
While Russia has not officially fielded anything similar we have seen efforts to adapt GP-25 under-barrel grenade launchers with shotgun adaptors and there has been at least one sighting, back in May, of an improvised slam-fire tube-shotgun mounted under-barrel on an AK-12. The shotguns even appeared on the Russia 1 state TV channel.
Since the latest photograph appeared there has been significant speculation as to whether it might be being used to defend against First-Person View (FPV) drones. This may be unlikely given the weapon’s short 7.75 (197mm) barrel, this length would limit its effectiveness in engaging more distant drones but might be useful in engaging approaching FPV drones- as a last ditch defence. This is something we’ve seen Russian combatants improvising weapons to deal with. The speed with which FPV drones close on their targets, however, would make multiple shots from the M26 unlikely due to its manual action. This would reduce the chances of successfully engaging an on-coming drone.
While any shotgun is better than no shotgun the units that the M26 has been seen with definitely have access to shotguns better suited to engaging drones. Where the M26 is more likely to be useful in Ukraine, is in its original role – as a breaching shotgun. Ukrainian units regularly find themselves operating in urban areas where quick access into rooms is key. Provided they have breaching rounds then the M26 might be most useful in this role.
M26 MASS Specs (from C-More Systems):
- Caliber: 12 gauge
- Chamber: 2-3/4″ or 3″
- Operation: Straight-Pull Bolt-Action
- Capacity: 3 or 5 Round Detachable Magazine
- Weight: 3 lbs (1.36 kg)
- Barrel Length: 7-3/4 in (19.7 cm)
- Overall Length: 16.5 in (41.9 cm)
- Cylinder Bore: Improved Cylinder
Update – 4/1/24: Tysk have shared some redacted footage of the M26 at the range along with the operator’s thoughts (machine translated):
“Experience shows the rifle’s effective range does not exceed 30 meters, and that already requires above average level of training.
Adding so much weight to the rifle increases the weight of the barrel too. I would argue one has to be quite a tough guy to stay in a ready position for long. Especially considering people nowadays cannot do the same even with an AK.
In my humble opinion, this weapon system has its niche and can even be useful as an independent piece but becomes too impractical when coupled with an M4.”
Update – 3/2/25: Mjolnir Group shared a photograph featuring an M26 in the standalone configuration.
Update – 2/3/25:
A recently shared video of a Ukrainian serviceman training with a US M26 MASS shotgun in the standalone configuration.
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The Armourers Bench 