[2] The mortar consists of a smooth-bored barrel with a breech and a breech-block frame, a frame with shock absorbers, mount with training and equilibrating mechanisms, a two-wheel traveling carriage with the suspension, a boom for changing from the firing to the traveling configuration, a baseplate and a towing bar with a lunette.

The mortar is normally towed, at a maximum speed of 40 km/h (25 mph), muzzle first by an AT-P, AT-L or AT-S tractor, which also carries the 11-man crew.

The large circular welded baseplate is lowered to the ground and packed with earth to provide a stable firing platform.

Large tongs/gripping pincers are used to lift the bomb from the trolley onto the projectile guide, with two men on each handle and the fifth steadying the fins.

[6] In addition to the standard F-864 high-explosive round used by the M240, a number of specialized munitions exist for the 240 mm mortar using 3M15 rocket motors to extend the range to 20 km (12 mi).

The variants include: The Soviet Union also developed laser-guided "Daredevil" rounds for precision strikes against fortifications.

A battery from the 1074th artillery battalion of the 108th Motor Rifle Division used 240 mm mortars towed by MT-LB tractors against the Muhajeddin forces of Ahmed Shah Massoud in the Charikorskoy and Panjshir valley, including the first use of specialized laser-guided "Daredevil" rounds.

After encountering DShK machine gun fire from one of Massoud's fortress, the 240 mm battery engaged the target and destroyed it in 12 to 15 minutes with 5 to 6 rounds, the mortar's high angle of fire proving effective in circumventing the fortress walls where 122 mm howitzer bombardments had previously failed.

Troops reported that the mortar was highly accurate and usually a single hit sufficed to destroy a target; furthermore, the heavy shells were little affected by weather conditions.

Reports of M240 mortar use became scarce after 2012, possibly because of depletion of munitions stock, but in 2015 and 2016 the exploded casings of two dozen rocket-assisted 3O8 240 mm shells were identified in the suburbs of Damascus, as well as in East Ghouta and Douma, accompanied by un-exploded O-10 fragmentation cluster munitions, which had never before been confirmed used in combat, causing some to speculate their employment may reflect renewed Russian support.