RX-77D Guncannon Mass Production Type – MechaBay

The RX-77D Guncannon Mass Production Type was a mass production artillery mobile suit developed by the Earth Federation Forces for mid-range fire support operations. It was a mass production variant of the RX-77-2 Guncannon introduced during the final weeks of the One Year War.

The “R” in the model code meant it was a Federation model¹ and the “X” designated it as an experimental mobile suit. The “77” indicated it was the seventy-seventh experimental project in development, while the “D” suffix denoted it as a dedicated mass production variant optimised for combat effectiveness and manufacturing efficiency.

History

Deciding to produce and deploy medium-range fire support mobile suits to complement its close-combat RGM-79 GM units, the Earth Federation Forces took the plans and combat data from the RX-77-2 Guncannon prototype developed under Operation V and refined the design for mass production. The development process drew heavily from the RX-77-3 Guncannon Heavy Arms Type, which had already eliminated the expensive Core Block System.

The new RX-77D Guncannon Mass Production Type first came off the assembly lines in the last weeks of UC 0079. Due to its late entrance into the One Year War, the Guncannon Mass Production Type saw a somewhat limited production run, with two units assigned to the Scarlet team stationed aboard Federation vessels.

In December, U.C. 0079, during the Federation’s African Front Zeon extermination operation, at least two Guncannon Mass Production Type were assigned to the 6th Garrison, one was piloted by Captain Vince and the other by First Lieutenant Lydo Wolf. Wolf achieved notable success with his unit, painting it black and earning the nickname “Dancing Black Reaper” after destroying an entire Zeon mobile suit team and shooting down 21 enemy units within a week.

The mobile suit also saw service with specialised units including the White Dingo Team in Australia and the Nemesis Instructor Corps in North America. In U.C. 0081, two Guncannon Mass Production Types were seen defending Augusta Base from the Zeon Remnants group Invisible Knights.

Design

To cut costs, the costly and complicated Core Block System was removed, and the original Guncannon’s expensive Luna Titanium armor was replaced with more affordable titanium ceramic composite armor. This change significantly reduced manufacturing complexity whilst maintaining adequate protection for the mobile suit’s artillery role.

However, its performance was greatly increased with the addition of more verniers and more powerful rocket thrusters. The propulsion system generated a total thrust output of 93,500 kg, with the primary thrusters producing 26,500 kg each and supplemented by additional verniers for improved manoeuvrability.

To improve productivity, it shared many parts with the late production type RGM-79G GM Command and its armor was made of titanium ceramic composite. This parts commonality streamlined logistics and maintenance procedures across Federation mobile suit units.

To reduce blind spots and inertial momentum during movement and close-quarters combat, its back-mounted low-recoil cannons were made semi-retractable. Additionally, the ammunition feeding mechanism of the low-recoil cannons was simplified compared to the original Guncannon and relocated. These modifications enhanced the mobile suit’s combat effectiveness whilst reducing manufacturing complexity.

For precision firing, a stabilizer gear in the bottom-rear pelvic section could extend to the ground, improving the mobile suit’s stability. This feature allowed the Guncannon Mass Production Type to achieve greater accuracy during sustained artillery bombardments.

Armaments

The RX-77D Guncannon Mass Production Type’s standard weapons were twin 200 mm cannons for artillery support and 60 mm vulcan guns for close-range defence.

60 mm vulcan guns

A pair of fire-linked 60 mm gatling vulcan guns were mounted on either sides of the Guncannon’s head. These rapid-fire weapons served multiple purposes, providing defence against incoming missiles and light aircraft whilst also offering suppressive fire against enemy mobile suits at close range.

The vulcan guns were primarily used against light-armoured support units and could damage mobile suit sensors and joints through sustained fire. Their rapid rate of fire made them particularly effective for missile defence and area denial operations.

200 mm cannons

The Guncannon Mass Production Type’s primary armament consisted of twin 200 mm cannons mounted on the backpack over the shoulders. These weapons provided the mobile suit with substantial long-range firepower, enabling it to engage targets at distances that exceeded visual range.

Because of these changes, its backpack was enlarged, but there were also improvements in productivity and ease of maintenance. The semi-retractable design allowed the cannons to be protected during movement whilst still maintaining rapid deployment capability when fire support was required.

Machine guns

Since the Guncannon had such heavy armor, it had no need for a shield and could carry two machine guns. The mobile suit could equip either a 90 mm bullpup machine gun or a 100 mm machine gun for medium-range engagements, providing flexibility depending on mission requirements.

These handheld weapons filled the gap between the long-range cannons and close-range vulcan guns, allowing the Guncannon Mass Production Type to engage targets at intermediate distances with sustained automatic fire.

Known pilots

Captain Vince (6th Garrison)
First Lieutenant Lydo Wolf (6th Garrison)
Various White Dingo Team pilots
Various Nemesis Instructor Corps pilots

Variants

White Dingo Team Custom

Custom-painted Guncannon Mass Production Type units were also used by the White Dingo Team in Australia featuring distinctive team markings and colour schemes.

Behind the scenes

Artist Yutaka Izubuchi initially designed the RX-77D as an update to the dated design of the original RX-77 Guncannon during the development of Mobile Suit Gundam 0080: War in the Pocket. The design represented a more modern interpretation of the artillery mobile suit concept.

The Guncannon Mass Production Type eventually became the basis for the RGC-83 GM Cannon II. This established a direct lineage from the original Project V designs to later Federation artillery mobile suits.

Appearances

Mobile Suit Gundam 0080: War in the Pocket
Mobile Suit Gundam: Battle Operation 2

External links

RX-77D Guncannon Mass Production Type on MAHQ
RX-77D Guncannon Mass Production Type on the Gundam Wiki

Federation in Japanese is renpou, hence the use of “R”. ↩