The mortar had an early form of Krupp horizontal sliding-block breech and it fired separate-loading, bagged charges and projectiles.

The downside was that high-angle indirect fire was harder to aim correctly so more mortars would be needed to defend an area from attack.

However, if the area was constrained by geography like a port at the mouth of a river the navigation channels could be measured ahead of time and firing ranges calculated.

The mount consisted of a rectangular steel firing platform with a pivot at the front and two wheels at the rear to give 360° of traverse.

The M1877 was designed with the lessons of the Franco-Prussian and Russo-Turkish war in mind where field guns with smaller shells and limited elevation had difficulty overcoming fortifications.

These consisted of twelve rectangular plates connected with elastic links and are visible in many photographs of World War I artillery from all of the combatants.