A 60mm practice round launched from an M2 US 60mm mortar is caught in flight as it soars towards its predetermined impact area only moments after launch.
The LMT M203 we obtained used a 9-inch barrel and used a rail mount. It is a good fit with this early Predator P-12SX Rail from POF-USA. After a few years of shooting there is no noticeable wear on either unit.
Because so many of the subcaliber rounds use black powder as a propellant it is important to clean and maintain your grenade launcher and host firearm well. This is a simple and effective “pull through” brush the author uses for 40mm barrel cleaning.
A few 40mm subcaliber devices. From left to right: 20-gauge to .410 (combined for 40mm to .410), 40mm to 20-gauge, 40mm to 12-gauge, 40mm to 26.5mm.
The addition of a Stag Arms, left-hand, removable carry handle allowed the easy use of a standard quadrant sight with very good results.
A 40mm/12-gauge subcaliber unit with a few specialty rounds of several that are available.
A small sample of the 26.5mm rounds that can be fired in an M203 Grenade launcher with a 40mm/26.5mm Subcaliber Unit (pictured standing in front of boxes). Left to right: illuminating parachute, white single star, blue smoke, black smoke, green single star, orange smoke.
Hornets Nest 40mm round. It is a subcaliber unit that fires ten .22 LR rounds, one from each of the 10 rifled barrels. A large rifle primer is used to initiate the firing by shooting the M203 in the normal manner.
The internals of the Hornets Nest round. The barrel, the striker and the end-cap.
We tested the Hornets Nest at several different distances and the results turned out to be quite interesting. Here are 3 average groups from 3 different distances. Tested at 10 yards, 15 yards and 20 yards it was recorded that every 5 yards in distance resulted in a small 1-inch increase in group size.
The contents of the 3-F-8 Mortar Subcaliber Device. Along with 20 subcaliber projectiles (A) is the barrel (B), the 4.2in adapter (C), the 81mm adapter (D), the 60mm adapter (E) and several cleaning and assembly tools.
Installing the subcaliber device into the M2 60mm mortar tube to prepare for launching small projectiles.
Left to right. The first frame is the initiation of the launch by dropping the projectile down the tube. The center frame captures the round as it breaks the skyline. The last frame actually captures the round as it impacts the little 24-inch target area and bounces up, sideways.
An assembled 60mm Mortar Subcaliber Projectile above one ready for assembly. Below are original boxes of the special propellant charges. The front load serves as a spotter charge. These are only low-powered blanks and it is important to know that the use of powerful blanks or live ammunition can damage the unit and have the potential to cause injury.
A 60mm practice round ready for launch. These rounds are cleaned up and reloaded for unlimited use as long as it can be located after firing. Center: Just out of the pipe. The photo was snapped milliseconds after this round is launched towards the impact area. Right: A typical find when we missed the intended target area.