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RGM-86R GM III

Mass production general purpose mobile suit developed by the Earth Federation.
Jenxi Seow Published 20 Jun 2025 Updated 20 Jun 2025
RGM-86R GM III

The RGM-86R GM III was a mass production general purpose mobile suit developed by the Earth Federation Forces as a successor to the RMS-179 GM II.

The “R” in the model code meant it was a Federation model and the “GM” denoted it was a Gundam mass production mobile suit. The “86” in the model code indicated it was developed in UC 0086, and the “R” suffix denoted it was a revised model.

The GM III was developed in accordance with the “GM III Plan” and represented a major upgrade over its predecessors, incorporating new technologies while maintaining productivity.

History

The RGM-86R GM III was introduced during the First Neo Zeon War in UC 0088 and served as the mainstay mobile suit in the Earth Federation’s military forces until the UC 0090s. Unlike the RMS-179 GM II, which was only a minor improvement over the original GM, the GM III was a major upgrade.

The GM III design proved to be a major success, and the model remained one of the EFF’s mainstay mobile suits for several years. By then, the GM III was being slowly replaced by the new RGM-89 Jegan series.

During the Second Neo Zeon War in UC 0093, several GM IIIs were deployed by the Earth Federation Forces’ 88th Fleet to assist in stopping Axis from dropping onto Earth. In UC 0096, the GM IIIs were still in service and fought against the Zeon remnant forces during the attack of Dakar and later at the Torrington Base.

In UC 0112, the Gleam Black Guns (GBG) mercenary group was hired by Oiel Raddegger to assist him in stealing data from F90 Team B’s test mission. The GBG’s customised GM IIIs, led by a Full Armor GM III, destroyed several FD-03 Gustav Karl units and RGM-109 Heavygun units, as well as heavily damaging the F90 Gundam Unit 2, resulting in Team B’s disbandment.

Design

The GM III was developed in accordance with the “GM III Plan” as a successor to the RMS-179 GM II. By incorporating new technologies while maintaining productivity, the GM III acquired performance equal to or higher than the RX-178 Gundam Mk-II’s in some areas.

The GM III incorporated a more powerful reactor, better sensors and armour, and a 37 percent increase in thruster speed thanks to a backpack design based on the one used on the RX-178 Gundam Mk-II. The GM III could also be fitted with a variety of missile launchers, giving the mobile suit a much more flexible mission role as either a close combat or fire support unit.

Its backpack was a mass production model of the Gundam MK-II’s, and mobility and manoeuvrability had exceeded the level of existing mass production machines. Although this backpack had a slightly different shape, it maintained the same functions as the Mk-II’s while improving cost performance, and the docking mechanism with the FXA-05D G-Defenser remained.

The GM III had an ultracompact Minovsky power plant that generated an output of 1,560 kW. It had rocket thrusters that generated 81,200 kg of thrust total with four main thrusters rated at 20,300 kg each, plus eight vernier thrusters/apogee motors. The mobile suit featured a panoramic monitor/linear seat cockpit in its torso and was armoured with titanium alloy and Gundarium alloy materials. Its sensors had a detection range of 10,900 metres.

Armaments

The GM III’s standard weapons were two 60 mm vulcan guns for close-range combat and two beam sabers for melee combat.

60 mm vulcan guns

A pair of shell-firing armaments were built into the head. These guns had low offensive power and were only used to restrict enemy movement and lay down a wall of suppressive fire due to their rapid rate of fire. They were ideal for shooting down small, lightly armoured targets such as missiles and attack vehicles.

Beam sabers

The GM III had two beam sabers stored in recharge racks in the backpack, each with a power rating of 0.4 MW. The beam sabers used an I-field to contain Minovsky particles within the shape of a blade. Minovsky particles broke down matter at a molecular level, meaning that the beam saber could cut through almost any material.

The beam sabers were hand-carried when in use and recharged with Minovsky particles from the mobile suit’s reactor when stored in the recharge racks.

Beam rifle

An updated version of the BR-S-85-C2 Beam Rifle used by the GM II and Nemo. Its appearance and manufacturing cost were almost the same as the older version’s, but its output was increased by about 50% to 2.8 MW. However, its usability had not been improved, and issues about its endurance remained.

Beam javelin

Due to its long handle, the beam javelin had a long reach, providing a considerable advantage in close quarters combat. It could also be used as a throwing weapon. Unlike the one used by the Gundam, this model was a mass produced version and its handle could not retract for functioning as a beam saber.

90 mm GM rifle

A portable, mobile suit-use 90 mm rifle built based on the “system weapon” structure. Its effective range and accuracy were superior to the HWF GMG·MG79-90mm machine gun. With the extended barrel, the GM Rifle saw a 15% increase in muzzle velocity, leading to increased armour penetration capability.

Shield

The GM III used a shield for defence that was mounted on either forearm. The shield was able to withstand beam attacks and featured an anti-beam coating on its surface. An alternate shield model used by GM III units in the UC 0090s was the same shield as used by the RGM-89 Jegan, which featured a pair of twin missile launchers.

Missile pods

The GM III could be equipped with various missile launchers to enhance its mission flexibility:

  • 4-tube medium missile pod – Two units could be mounted on the shoulders, with 3 rounds of ammunition per tube
  • 15-tube small missile pod – Could be mounted on the waist

Known pilots

  • Bosch Weller
  • Yamaguchi

Variants

Several variants of the GM III were developed:

  • RGM-86R Nouvel GM III – A further improvement with enhanced reactor output, redesigned head and chest, and additional mobility enhancements
  • RGM-86R-FA Full Armor GM III – A heavy armour version with additional weapons and armour similar to the FA-78-1 Full Armor Gundam
  • RGM-86EW GM III Early Warning Type – An early warning variant with enhanced sensor equipment

Behind the scenes

Okawara Kunio was the original mechanical designer for the Gundam ZZ version. The design was later updated for the novel and OVA Mobile Suit Gundam Unicorn.

The GM III represents the culmination of the GM series development, incorporating lessons learned from previous iterations and featuring performance rivalling some Gundam-type units of the era.

Appearances