RGC-80 Prototype GM Cannon

The RGC-80-1 GM Cannon Test Type is an experimental Earth Federation Forces artillery mobile suit. Although it was never actually seen in any animated series the GM Cannon Test Type is an official Mobile Suit Variation.

When the Earth Federation Forces finally began mass-producing their own RGM-79 GM model of mobile suits in the final months of the One Year War it was decided that there would need to be a mid-range fire support unit to properly supplement their close-range GM forces. Rather than wasting the time designing a new mobile suit, and then putting a strain on resources setting up the new production lines that would be necessary to build them, the Federation Forces decided to simply produce a design variant of the standard GM to fill the void in their ranks.

The first GM redesign created in the attempt to solve the Federation's problem was the RGC-80-1 GM Cannon Test Type. The GM Cannon Test Type was little more than a normal GM with a RX-77-2 Guncannon's head, backpack, and dual 240 mm shoulder-mounted cannons. However there was a critical flaw in this first design. The dual shoulder cannons were far too heavy for the light frame of the GM, and when the cannons were fired the unit experienced severe recoil and balance problems. The GM Canon Test Type was deemed insufficient, and the Federation's researchers and engineers went back to rework the design, producing the RGC-80 GM Cannon as their final product.