The GP-25 is a soviet grenade launcher that is made to be mounted on AK's.
An RGM-40 is also included, the standalone version of the GP-25
Fires an anti personel caseless 40mm round
To fire and load it just take the explosive, shove it into the barrel at the front, with the little stick part facing inwards, grab the invisible part under the trigger and trigger guard and press F and wait a little.
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