RGC-83 GM Cannon II – MechaBay | Mobile Suit Gundam 0083: Stardust Memory

The RGC-83 GM Cannon II was a mass production general purpose mid-range support mobile suit developed by the Earth Federation Forces following the One Year War. It was the successor to the RGC-80 GM Cannon, incorporating advanced technology and improved firepower.

The “R” in the model code meant it was a Federation model¹ and the “GC” designated it as a Gundan-derived cannon mobile suit. The “83” in the model code denoted that it was developed in UC 0083.

History

In the last weeks of the One Year War, the Earth Federation Forces had developed the RGC-80 GM Cannon as a much-needed medium-range fire support variant of its standard RGM-79 GM mobile suit. However, its late introduction into the war resulted in a rather limited production run.

Following the war’s end, the EFF began a massive reconstruction of its military, and one of their latest GM models, the RGM-79N GM Custom, served as the basis for the new RGC-83 GM Cannon II. The mobile suit was the culmination of the Federation’s artillery support mobile suit development and incorporated lessons learned from the original GM Cannon’s service.

The RGC-83 GM Cannon II was manufactured by the Federation’s Jaburo factory. On October 14, U.C. 0083, following the theft of the RX-78GP02A Gundam GP02A “Physalis” from Torrington Base, Vice Admiral John Cowen ordered Eyphar Sinapus, Captain of the MSC-07 Albion, to pursue the stolen Gundam. To assist him on this mission, three C-88 Medeas from Jaburo delivered several new mobile suits and pilots to the Albion, including two GM Cannon IIs.

One of the GM Cannon IIs was piloted by Immortal 4th Team member Chap Adel and the other was piloted by Chuck Keith, a rookie pilot from Torrington Base. Both suits saw action on October 23, when the Albion’s mobile suit team engaged the Kimberlite Forces, a group of Zeon Remnants based in East Africa.

During the Delaz Conflict, the GM Cannon II units aboard the Albion participated in several engagements. After the Albion departed from Von Braun, former Zeon mobile armor pilot Kelley Layzner deployed in the MA-06 Val Walo and intended to destroy the RX-78GP01Fb Gundam GP01Fb “Zephyranthes Full Burnern” to prove himself. When Kou Uraki deployed in the GP01Fb to stop Kelley, the latter trapped the Gundam using the Val Walo’s Plasma Leaders. At this point, Keith deployed in the GM Cannon II and fired its beam cannons at the Val Walo, but ended up missing. He then fired his rifle at one of the Plasma Leaders, destroying it and freeing the GP01Fb which eventually destroyed the Val Walo.

Like the GM Custom, there was a plan to mass produce the GM Cannon II, but due to issues such as cost and the fact that the machine was meant to operate alongside the GM Custom, only a few units were actually deployed. After the Delaz Conflict, the project itself, including its development staff, was placed under the control of the Titans. The GM Cannon II’s production was halted and a direct successor to it was never developed.

Despite its limited production, some GM Cannon IIs continued to serve beyond their initial deployment. In U.C. 0084, a GM Cannon II piloted by Titans’ mobile suit pilot, Agar, was used to support the RGM-79Q GM Quels hunting Zeon remnants during a riot in the lunar city of Ayers. In U.C. 0087, a GM Cannon II was operated by AEUG along with the GM Custom, and they were deployed from the Argama during the Gryps Conflict.

Design

The successor of the RGC-80 GM Cannon, a medium-range support mobile suit developed in the late stage of the One Year War, the RGC-83 GM Cannon II was based on the RX-77D Guncannon Mass Production Type and inherited the Chobam Armor concept of the RX-78NT-1 Gundam NT-1. The GM Cannon II, with its pair of shoulder-mounted beam cannons, more closely resembled the RX-77-2 Guncannon prototype from the war than it did the original GM Cannon.

Thanks to improvement in technology and productivity, the GM Cannon II was installed with a powerful generator, allowing it to be equipped with two shoulder-mounted beam cannons. This made it the first mass production unit to have integrated high-powered beam cannons. These beam cannons were usually powered by the generator itself, but could also be powered by the two Energy CAP mounted on its backpack.

The GM Cannon II featured significantly improved protection over its predecessor. The GM Cannon II was also armored with a thick layer of chobham armor, the same experimental armor tested on the RX-78NT-1 Gundam NT-1 Alex near the end of the One Year War. This Chobham armour was a composite armour system that provided superior protection against both kinetic and energy weapons.

However, the enhanced protection came at a cost. This massive armor application greatly reduced the GM Cannon II’s speed and mobility. The mobile suit was designed to operate as a fire support unit rather than a front-line combatant, so this trade-off was considered acceptable for its intended role.

It carried the same standard GM rifle and shield as the GM Custom, and incorporated a more powerful generator to charge its beam cannons. The mobile suit retained the general layout and internal systems of the RGM-79N GM Custom, ensuring compatibility with existing maintenance procedures and spare parts.

Armaments

The GM Cannon II’s armament was designed for medium-range fire support, combining traditional projectile weapons with advanced beam technology.

60 mm vulcan guns

A shell-firing armament built into both sides of the head. The 60mm bullets rapid-fired from the two Vulcan guns are effective in close combat, restricting enemy movements, intimidation, etc. These fire-linked gatling vulcan guns provided close-range defensive capability and could be used against lightly armoured targets or incoming missiles.

Beam saber

A beam weapon for close combat. It is a small device held in the mobile suit’s hands when operated and is powered by a rechargeable energy capacitor. It emits a blade of plasma contained by an I-Field and can cut through any armor not treated with anti-beam coating. The beam saber was stored in recharge rack in left forearm, hand-carried in use and rated at 0.38 MW.

Beam cannons

The GM Cannon II’s primary armament consisted of two beam cannons mounted in the backpack over the shoulders. These represented a significant advancement over the projectile cannons used by the original RGC-80 GM Cannon. The beam cannons could deliver devastating firepower at medium to long range, with energy beams capable of penetrating most mobile suit armour.

A sighting device located on the pilot seat’s headrest could be used to aim the beam cannons, providing improved accuracy for long-range engagements. The cannons could be fired independently or together, allowing for flexible tactical employment.

GM rifle

The GM Cannon II was equipped with the HFW-GR·MR82-90mm GM rifle, the same weapon used by the RGM-79N GM Custom. This bullpup-configured beam rifle provided reliable medium-range firepower and served as the mobile suit’s primary hand-held weapon when the beam cannons were inappropriate for the tactical situation.

Shield

For defense, the GM Cannon II uses the same shield as the RGM-79N GM Custom, which is an updated model of the one used by RGM-79G GM Command. The shield could be mounted on either forearm and provided additional protection against enemy fire. The shield also featured mounting points for spare energy capacitors, allowing extended operations away from supply bases.

Optional armaments

The GM Cannon II could be equipped with the BOWA BR-S-85-L3 sniper beam rifle for long-range precision engagements, taking advantage of its stable firing platform and advanced sensors.

Known pilots

Chuck Keith
Chap Adel
Ben Wooder
Agar

Variants

RGC-83 GM Cannon II [Lucien Bendt use]

A customised variant operated by Lucien Bendt during the Advance of Zeta period, featuring modified weapons configuration and unique camouflage paint scheme.

RGC-83 GM Cannon II [White Coral]

An upgraded version of Lucien Bendt’s GM Cannon II, the GM Cannon II [White Coral] has had its dazzle camouflage paint removed in favor of a more traditional color scheme. Because it is a commander-type unit, the head communication antenna has also been enhanced. The main improvements were that the beam cannon on the right side was replaced with a new mega particle cannon, the beam cannon on the left side was replaced with a ranging device, and a retractable antenna was added to the shoulder armor.

Behind the scenes

Original mechanical designer(s): Hajime Katoki (Gundam0083 version), Yasuo Ohtagaki (Gundam Thunderbolt manga version). Katoki Hajime was responsible for the mobile suit’s design in Mobile Suit Gundam 0083: Stardust Memory, working alongside Shoji Kawamori on the series’ mechanical designs.

In the first opening of 0083, the GM Cannon II’s beam cannons are shown firing yellow beams. However, they are depicted as pink in the series.

Gunpla

Bandai released a High Grade Universal Century (HGUC) 1/144 scale model of the GM Cannon II in June 2011 as kit #125. The model features articulated beam cannons, a beam saber stored in the forearm, and comes with the standard armaments including the GM rifle and shield.

Appearances

Mobile Suit Gundam 0083: Stardust Memory
Mobile Suit Gundam: Encounters in Space

External links

RGC-83 GM Cannon II on the Gundam Wiki
RGC-83 GM Cannon II on MAHQ

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