We used to use a 12 guage CS round here in the U.K. Police called a Barricade Penetrating Cartridge or 'Ferret' for short. They were made in the U.S. by AAI Corporation, Baltimore, Maryland. The cases were made by Peters and had a charge of black powder. There was a bomb shaped projectile made of plastic which containes 3cc. of liquid CS. It was for use for firing through glass windows or thin skinned doors where it would burst open and flood the room. Very effective! Lagopus.....