The 9mm Peruvian MGP-87 is a fascinating weapon. It was developed in the 1980s by the Peruvian military and used by the Navy and local police forces. About 16,000 were produced. It is notable for its ability to launch rifle grenades. The photo above shows the MGP-87 fitted with its grenade launching perforated sleeve and a frag grenade ready to be fired.
South American gun expert Ronaldo Olive wrote an article about the Peruvian MGP-87 for the 1995 Edition of SPECIAL WEAPONS for Military & Police. He was kind enough to let us publish it for you all to read.
The photo below shows a number of variations of the gun …
Many thanks to Ronaldo Olive for the photos and information.