Soon after introduction of the Type 10 grenade to front line combat troops, a number of issues arose.

When hand-thrown, instability and inaccuracy of the fuse mechanism made the Type 10 almost as much of a menace to the thrower as to the recipient.

The fuse was a percussion-activated delay type, initiated by pulling out a safety pin and striking the top of the cap.

[3] When used as a rifle grenade the fuse activated automatically, as the plunger was pushed in against a weak creep spring by the force of the launch.

Additionally, the Type 91 could be used as a booby trap by removing the safety pin and setting under a floorboard or chair.

The cartridges are fired from the rifle and the wooden bullets are trapped by the tail-fin assemblies launching and arming the grenade.

In addition to a four-second delay, the Type 97 had no provisions for attaching a propellant base for firing by grenade projector.

When the Type 97 with its shortened delay came into production and was being delivered to front line combat units, the Japanese Army continued to use the older Type 91 grenades as hand-thrown weapons, in addition to rifle and grenade projector use.