Here's some of the key info from this feature, which discusses the four phases of wartime GM production. This is derived purely from the classic MSV info and the MSV-R series, and so it takes absolutely no account of the other variants featured in Gundam 0080, The 08th MS Team, video games, comics, or your favorite fanfic.
MSV mavens may recall that the old MSV books referred to two production runs of the RGM-79; 42 units of an "early production type", and 288 units of a "later production type". The most recent repackaging of that info in the Master Grade GM Ver.2.0 kit manual actually uses the terms "first production type" and "second production type" instead, which helps us to reconcile the old MSV and new MSV-R accounts. If we put all this info together, we'd probably have something like this:The first production run of the RGM-79 took up about 70 percent of the production lines centered at Jaburo, which were put into full operation. Some were also produced at Luna II, but the number was small compared to Jaburo, and full-scale production of the RGM-79 at Luna II only began with the second production run, which included variations.
In addition to the normal RGM-79, a few trainer types were also produced during the first production run. These were used for training pilots and transitioning them from other machines.
As the RGM-79 was gradually deployed on the front lines, pilots began to demand performance improvements, due to its lack of firepower and poor mobility against the latest MS-07 and MS-09 types. But the Federation Forces were focused on mass production of the RGM-79 type, and tended to ignore these demands. The RGC-80, and an RGM-79L type with improved mobility, were included in the second production run as supplemental orders. However, they accounted for fewer than one-tenth of the total number.
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During the third production run, the RGM-79 and RGC-80 were produced at Jaburo. At Luna II, production of the RGM-79SC high-end model began in addition to the RGM-79, yielding 24 early production units.
After the war, it was revealed that the third production run also included the RGM-79V, which was developed for use by special forces teams. As these teams were organized in secret, and their activities were not disclosed, the production of these specialized machines was also a confidential matter.
The fourth production run began while the third was still in progress, but at this point the production system itself was somewhat altered. Thanks to their counteroffensive operations, the Federation Forces had recaptured many military bases and manufacturing facilities and begun refitting them, thus expanding their production sites.
Licensed production of some key RGM-79 parts began at various places. On Earth, where the RGM-79 had taken up 70 percent of Jaburo's production lines, this was reduced to 40 percent as production of ships and aircraft resumed. The eliminated RGM-79 production lines were relocated to the recaptured California Base, and during the fourth production run, roughly 60 percent of all units were manufactured at the California Base.
The RGM-79SC, which appeared in the final stage of the war, was developed for skilled pilots. Its basic design began just after the first production run of the RGM-79 was completed, and it was meant to be included in the second production run. The large number of design changes, however, required changes in operating system maintenance as well, and so it was postponed. Higher performance had resulted in lower production efficiency, although not to the same degree as with the RX-78.
First Production Run: 42 units of RGM-79 and TGM-79. Produced mainly at Jaburo, plus some at Luna II.
Second Production Run: 288 units of RGM-79, RGM-79L, and RGC-80. Produced at Jaburo and Luna II. RGM-79L and RGC-80 account for less than 10 percent of the total.
Third Production Run: Total unknown. Includes RGC-80 produced at Jaburo, 24 units of RGM-79SC produced at Luna II, and the secretly developed RGM-79V.
(According to the RGM-79V profile text, the first 12 units were created by modifying existing machines, so those would presumably have been part of the second production run. This is followed by two more rounds of RGM-79V production, which presumably take place during the third and fourth RGM-79 production runs, resulting in a grand total of 88 units.)
Fourth Production Run: Total unknown. Includes the RGM-79HC and RGM-79KC, developed from on the previous SC type. Jaburo production is scaled back, and the majority of this production run takes place at the California Base.
-- Mark