A caulking gun has a conventional tubular – shaped cartridge holder with a ratchet mechanism and ratchet able person, and is used with a collapsible cartridge having a nozzle end, a hollow tubular body joined to the nozzle end having walls of the tubular body at the end opposite the nozzle end having a shape which pushes the tubular body walls ahead of it to a collapsed condition to squeeze sealant material out through the nozzle end when the push in end is pushed by the piston of the Caulking Gun. In a preferred embodiment the collapsible cartridge is used with a sleeve member which is inserted and retained in the cartridge holder of the Caulking Gun.
The sleeve member has a removable/displaceable retainer position, a tubular holder body and a portion which is pushed by the piston of caulking gun. With the retainer portion removed, a new cartridge is inserted in the tubular body of the sleeve member, then the retainer portion removed, a new cartridge in the body of the sleeve member, then the retainer portion is re-attached and the sleeve member is inserted in the cartridge holder. The caulking gun is operated in the conventional manner to push the push in end of the cartridge to dispense sealant. When the cartridge is spent, it can be removed from the sleeve member without any soiling of the caulking gun, the user hands or exposed surfaces.