Figure 54 of the US Army Operator's Manual for the AK-47 Assault Rifle.
[1].
The AK-47 can mount a (rarely used) cup-type grenade-launcher that fires standard Soviet RGD-5 hand-grenades. The soup-can shaped launcher is screwed onto to AK-47’s muzzle. To fire…
First, insert a standard RGD-5 hand-grenade into the launcher and then remove the safety pin…
Second, insert a special blank cartridge into the rifles chamber…
Third, place the butt-stock of the rifle on the ground and fire from this position.
The maximum effective range is approximately 150 meters.