The mortar utilized a new nickel-steel alloy of greater strength than other cast cannons, though it lacked a recoil mechanism.

While the gun was more effective than previous models, it was soon phased out because of improved field artillery and counter-battery fire, though it remained in service in limited numbers throughout the war because of heavy German losses.

[2] The theorists hadn't foreseen that trenches, barbed wire, and machine guns would rob them of the mobility they had been counting on, and like in the Franco-Prussian and Russo-Turkish wars the need for high-angle heavy artillery to deal with fortifications reasserted itself.

Since aircraft of the period were not yet capable of carrying large diameter bombs, the burden of delivering heavy firepower fell on the artillery.

The combatants scrambled to find anything that could fire a heavy shell, meant emptying fortresses and scouring depots for guns held in reserve.

The Mrs 99 was fairly conventional for its time and most nations had similar mortars such as the Mortier de 220 mm modèle 1880 or Mortaio da 210/8 D.S.

This meant that the Mrs 99 could be smaller in diameter, lighter in weight, fire heavier projectiles, and have longer range.