Dawn of the Zaku

[Gelgoog Jager]

Regarding the Zaku Cannon's deployment, isn't it a bit pointless for Zeon to develop one such unit by late September/October?

Zeon first finds out about the Guncannon on September 23rd. By then the MP of the Dom has already begun. Wouldn't it make more sense to use that as the base model for the new artillery MS. Incidentally, the first type of Dom Cannon, the MS-09K-1, has a single long cannon like the Zaku Cannon:

http://gundam.wikia.com/wiki/MS-09K-1_Dom_Cannon

However, the MS-09K-2 has a set of twin middle cannons, which seems to attempt to serve the same role as a Guncannon:

http://gundam.wikia.com/wiki/MS-09K-2_% ... Dom_Cannon

How about this: The MS-06D and MS-06K are developed as localized MS and deployed around the same time at the beginning of the war, with a focus on Desert areas. By late September, MP of the Dom begins, and California base begins preparing localzied variants of the Dom, based on the YMS-09. We know the YMS-09D is developed from a MS-09A, so the same could be true for the prototype MS-09K-1, which would explain is regualr paint scheme. This unit uses data from the Zaku Cannon, and therefore has a single long barrel cannon and serves as a long range support unit.

However, information soon arrives about the Guncannon, and the focus changes into developing a Dom variant that can fulfill the same role as the former (middle range support unit). The MS-09K-2 is developed and at that point these units are painted in desert colors for their deployment along MS-09D units.

Some interesting coincidences are that both MS-09K units use the same arm mounted buckler shield and 3-tube missle launcher of the MS-06D:

http://gundam.wikia.com/wiki/File:MS-06D_-_MSV.jpg

Zeon color schemes of the Zaku Cannon strongly hint an intended use in desert areas:

http://gundam.wikia.com/wiki/MS-06K_Zaku_Cannon

Also, some MS-06D units have been seen with what looks like a handheld version of the MS-06K's back mounted big guns, indicating the existance of that weapon by the time the MS-06D was deployed:

http://gundam.wikia.com/wiki/File:Ms-06d-karakal.jpg
http://gundam.wikia.com/wiki/File:Zaku_Desert_Type.jpg

And unlike its ZZ cousin, the MS-06D doesn't seem to be regularly (if at all) equipped with long range weapons, like a Zaku Bazooka or Magella gun, which could also hint an intended use in concert with Zaku Cannon. One similar example is indicated in the background information of the Zssa and Gallus J in ZZ. The case MS-06C also provides a similar situation of squadrons made up of assault teams and artillery teams.

Finally, hypothetically speaking, if I had to think of some unique factor about Ian Greydon's Zaku squadron that would make them unqiue by the end of the war, given that they are escaping from California Base, it would have been amusing to have them being the hinted Zaku Cannon units equipped with beam cannons, which if IIRC, in another thread were mentioned out in the background information of the Zaku I Sniper's manual (though the same source seem to indicate that such units weren't actually completed), which would essentially use the same research and technology.

In such case we could even consider that after the information of the Guncannon was otbained, a research group was tasked with copying the Guncannon's twin cannons (MS-09K-2), while a different group was tasked with creating a support unit with a ranged beam weapon. The MS-05L could be a by-product or even an initial crude attempt at this.

[Zeonista]

It seems like not every "horned" squadron leader is an S type - there's supposed to be a "horned" version of the standard F type, and we've seen horned versions of the F2, K, R, and so forth. If we have roughly 1,200 F types, there'd almost be enough S types for every squadron leader, but if we want to mix these in with the regular J type as well then they'd be a bit more scarce.

I'm actually skeptical about that figure of 100 S types - it's just supposed to be an expensive stopgap until the R type goes into production, so it seems weird that there are more S types. Something on the order of 50 units (like the equally rare G type) seems more rational, but I guess we could always fudge this by saying that the tally includes the FS type as well.

The "horned" MS for the officers do seem more often than not to be officer-upgrade versions of whatever Zaku is in the unit in question. The S-types are simply not that numerous, especially on Earth! I'd say the S-types were parceled out to the aces after Loum, but were retained by the ZMF's space forces. The ZEF didn't need them in the invasion, and that role of ace pilot machine would be filled by the Goufs, anyway. The pilots of the S-types eventually were assigned the R-series MS, and the S-types were withdrawn from service.

And yes, the notion that Zeon would publicly announce its production numbers by displaying them on publicity "photos" is implausibly convenient. We absolutely no evidence that these are serial numbers in the first place, let alone the serial numbers of the final units. That said, they don't seem like bad ballpark estimates.

Plausible convenience works when doing production estimates, so I have no quarrel with your earlier figures. I divided all the figures by 3 to get a general sense of unit numbers, and they turned out to be very possible & plausible. Add in the Dom teams and the officers in Goufs, and the ZMF had a fair number of MS on Earth, even not including the Marine MS! Allowing the R-series, the bulk of the F-series, and the Rick Doms in space, and the ZMF had enough MS to fill out their ranks in the fleets and the major bases.

Here's another way of looking at the F type production run: As per Gundam Century, the production run of the F type (3,246 units) is about 40% of the total MS-05 and MS-06 production (8,000 units). If current sources have halved that latter figure - to about 4,000 units - then the production run of the F type should be halved as well, so we'd expect something like 1,600 F types. Since more recent productions have introduced the idea of a later "F2" model, which didn't exist when Gundam Century was written, we could reasonably take that as the target number for the F and F2 combined.

I am leery of tossing the F2 into the basic F's production run, since it was different enough in construction and performance to warrant a separate designation. I'd say the F2 had its own modest production run, which continued after the war since the MS could be used to arm the Republic of Zeon until they were given Hizacks (as per Ecole du Ciel). Delaz Fleet could have had F2 units because his fleet was resupplied before Aboawaku, and the UMP allowed him to continue them in service afterwards without having to worry about spare parts. (The 0080 & 0083 OAVs' habit of cheerfully using the designs du jour everywhere regardless of logistics is of little help here. ) OTOH I am content to fold all the Zaku Kai production into your existing production figures because aside from UMP compatibility, they were conversions of existing Zaku II.

Gelgoog Jaeger: It's not really pointless to develop the Zaku Cannon at a late date, because it was an adaptation to fit the circumstances. Unlike the Dom Cannon variants, the Zaku Cannon already existed as complete units, and could be deployed as anti-armor/MS units instead of AA units by mounting different weapons. They weren't especially good, but as stopgap measures they worked fine. And at least we know the Zaku Cannons existed as battle machines, and not as some exotic Dom prototype that might or might not have seen real combat.

I do not see the Zaku Cannon as being made as the Desert Zaku's support unit. Remember, it was developed as a specialized AA platform, and as I've said earlier, the Zakus themselves could carry all the support weapons required, until the Dom was produced and filled that support/assault slot rather nicely. I discount the paint scheme as well because as toysdream pointed out in his history above, the Zaku Cannon units were rotated into different combat zones, and were painted accordingly. The secondary armament is interesting, but instead of common relation as units, might instead be evidence that the Zaku units were given more short-range weapons as the OYW progressed to Zeon taking a more defensive stance. The arm missiles weren't main-use weapons, they were explosive shuriken meant to cover a retreat or reloading of the main weapon.

I must regretfully scotch the idea of energy weapon-armed Zaku Cannons through a complete lack of evidence. Not to mention the Zaku Cannon used the same Zaku II-series power plant that couldn't support a particle beam weapon. There is nothing to suggest that Ian Graydon used anything except the regular Zaku Cannon he was issued. He was just that good, probably because he must have realized what a great mid-range sharpshooter he had in his hands. However, I do like the idea of the Zaku I Sniper project being a parallel development on the idea of providing mid-range anti-MS support by using a particle beam instead of a conventional cannon.

[toysdream]

You know, that's an interesting theory. I don't want to reject it out of hand just because it requires us to throw out all of the known backstory for the Zaku Cannon (although, yeah, it does require us to throw out all the known backstory).

There are a couple of things I'd mention here. Regarding the Zaku Cannon's sandy colors, the old 1/100 kit manual comments as follows...

The first of the nine units was painted in sand colors, because it was expected that tests would be conducted in central North America or in western Asia, but later on a standard dark gray camouflage was applied as the region changed. Early on, when they were stationed at the California Base, they were all painted in the same colors as the first prototype unit. [...] Depending on the different combat areas, in addition to the standard gray camouflage, dark green camouflage colors were also applied for use in forest regions.

So there's one explanation. I guess Ian Graden's machine gives us an example of the dark green camouflage colors, but I don't think we've ever seen the supposedly standard dark gray. You're right, though, that the initial sand colors are pretty much identical to those of the basic Zaku Desert Type. Perhaps the dark gray camouflage would resemble the MS-07C-3?

As far as the timing relative to the Guncannon, it's possible that Zeon may have gotten some intelligence about this machine before they saw it in combat.

And speaking of the Dom Cannon, I'd note that the same backpack is attached to the Zaku Cannon that appears in 08th MS Team. So there does seem to be some kind of entanglement between all these machines.


But while we're floating weird theories, let me mention my own pet theory about the Zaku Cannon. You'll note that in many respects, it's an extremely unusual version of the Zaku, with a completely different exterior. Some of its unique features include...

* No head cables. The overall shape of the head is actually a lot like the Gelgoog Cannon.
* Chest cables attach to the upper chest, not the "belt buckle" seen in every other Zaku version.
* Chest vents! We don't see those on any other Zaku until the Hizack.
* Streamlined and angular limbs, with protruding joints at the knees.
* No backpack thrusters.
* Gouf-style leg thrusters. These actually look like a hybrid of the MS-06D and YMS-09 leg thrusters.

So they didn't just slap a new head and backpack on a standard Zaku - they appear to have built an entirely new machine! The question is why.

My personal theory is that the so-called Zaku Cannon is actually a cannon version of the legendary MS-06R-3 Zaku III (the one described in the MSV materials, not Okawara's M-MSV interpretation). After all, if the Gelgoog was intended for use in space and Earth, you couldn't gather test data entirely in space. Thus the Zaku Cannon was created to gather ground combat data for the Gelgoog, as well as testing equipment for the Gelgoog Cannon. That's why it has the same head as the Gelgoog Cannon, and why they attempted to equip it with a beam cannon (taking advantage of the higher output of the MS-06R-2 and R-3 series).

On the other hand, as I look at all the MSV designs side by side, I start to think that the Zaku Cannon also inherits a lot from the Prototype Dom - from the knees down, the resemblance is very strong. If anything, it seems like a chimerical hybrid of every other late-model Zeon machine, and I think it's such a weird-looking and unique machine that it really deserves a weird and unique back story.


EDIT: And now here's a really crazy theory that occurs to me. Assuming that the old MSV materials were correct that the Zaku Cannon was tested with a beam cannon pack...

What if the dainty little gun we usually see on the Zaku Cannon is the beam cannon pack!?

That would explain how the original "mass balance" problems were resolved - the original 180mm cannon that was intended for the MS-06J-12 is the huge contraption we saw in 08th MS Team, a gun so big and powerful that they ended up putting it on a Dom instead. Meanwhile, the Zaku Cannon is fitted with an early version of the Gelgoog Cannon's beam weapon, which would explain the close resemblance between these weapons (and the lack of resemblance between the Zaku Cannon's gun and any other shell-firing cannon).

This also explains why they're still using these in Zeta Gundam, too. A lot of sources claim that the Zeta version of the Zaku Cannon has a beam cannon, even though it looks just like the original weapon...

-- Mark

[Zeonista]

There are a couple of things I'd mention here. Regarding the Zaku Cannon's sandy colors, the old 1/100 kit manual comments as follows...

The first of the nine units was painted in sand colors, because it was expected that tests would be conducted in central North America or in western Asia, but later on a standard dark gray camouflage was applied as the region changed. Early on, when they were stationed at the California Base, they were all painted in the same colors as the first prototype unit. [...] Depending on the different combat areas, in addition to the standard gray camouflage, dark green camouflage colors were also applied for use in forest regions.

So there's one explanation. I guess Ian Graden's machine gives us an example of the dark green camouflage colors, but I don't think we've ever seen the supposedly standard dark gray. You're right, though, that the initial sand colors are pretty much identical to those of the basic Zaku Desert Type. Perhaps the dark gray camouflage would resemble the MS-07C-3?

The ZEF desert camo scheme is pretty good overall. With minor variations, it would work well for any dry, dusty battlefield conditions. The dark grey paint scheme reminds me of the Gouf H-8 somewhat, or the C-3 perhaps. I guess panzer grey works everywhere?

And speaking of the Dom Cannon, I'd note that the same backpack is attached to the Zaku Cannon that appears in 08th MS Team. So there does seem to be some kind of entanglement between all these machines.

I thought there was a connection somewhere, which makes it interesting! The Shuddering Mountain had some Doms as part of its force. Maybe somebody made a Zaku Cannon using a Dom Cannon backpack? It would explain the burly size of the cannon pack.

But while we're floating weird theories, let me mention my own pet theory about the Zaku Cannon. You'll note that in many respects, it's an extremely unusual version of the Zaku, with a completely different exterior.

My personal theory is that the so-called Zaku Cannon is actually a cannon version of the legendary MS-06R-3 Zaku III (the one described in the MSV materials, not Okawara's M-MSV interpretation). After all, if the Gelgoog was intended for use in space and Earth, you couldn't gather test data entirely in space. Thus the Zaku Cannon was created to gather ground combat data for the Gelgoog, as well as testing equipment for the Gelgoog Cannon. That's why it has the same head as the Gelgoog Cannon, and why they attempted to equip it with a beam cannon (taking advantage of the higher output of the MS-06R-2 and R-3 series).

EDIT: And now here's a really crazy theory that occurs to me. Assuming that the old MSV materials were correct that the Zaku Cannon was tested with a beam cannon pack...

What if the dainty little gun we usually see on the Zaku Cannon is the beam cannon pack!?

That would explain how the original "mass balance" problems were resolved - the original 180mm cannon that was intended for the MS-06J-12 is the huge contraption we saw in 08th MS Team, a gun so big and powerful that they ended up putting it on a Dom instead. Meanwhile, the Zaku Cannon is fitted with an early version of the Gelgoog Cannon's beam weapon, which would explain the close resemblance between these weapons (and the lack of resemblance between the Zaku Cannon's gun and any other shell-firing cannon).

This also explains why they're still using these in Zeta Gundam, too. A lot of sources claim that the Zeta version of the Zaku Cannon has a beam cannon, even though it looks just like the original weapon...

Holy crap, you might have just totally justified Gelgoog Jaeger's theory on the Zaku Cannon! It does all make sense, presuming the beam cannon pack is equipped on the Zaku Cannon. ANd you're right about the backpack details, the Zaku Cannon does not share the features that a shell-firing cannon would have, and the barrel always looked slim for its length, compared to the Magella Top or Gun Cannon. (See the Zaku Cannons in Gundam Unicorn #4, skinny barrels!)

A shoulder-mounted beam cannon would definitely be able to capitalize on the Zaku Cannon's incorporated AA-directed sensors and targeting system. It would definitely have made Ian-san a deadly ace, able to line up accurate medium-long shots with a stabilized beam gun against GMs equipped with short-range weapons, and Type 61 tanks with inferior targeting systems. The rocket pods that were the standard secondary equipment would then be used against the EFF's hover vehicles that would be fast enough to close the range, but not have the defensive armor needed to stop a medium-caliber missile. And given the Zeta Gundam reference, those Zaku Cannon units were equipped on a EFSF cruiser, which wouldn't necessarily use a MS with a shell-firing cannon, but would definitely take on some MS with beam cannons! It-it all makes sense....

[toysdream]

Yeah, the more I think about this theory, the more I like it!

I checked episode 4 of Gundam Unicorn, and there it's definitely being animated as a shell-firing weapon. On the other hand, at that point the poor old Zaku Cannon has been in service for almost 20 years, so it's not unthinkable that a fancy experimental beam cannon might have broken down by then and been replaced by a shell-firing lookalike.

Anyway, it turns out that the reason the cannon looks so much like a beam weapon is because it was originally supposed to be. Tipped off by the Japanese Wikipedia, I checked the "Anime Graph Book" where the MS-06D, K, and M first appeared, and the description attached to Okawara's original drawing says it's armed with an anti-air beam cannon. Apparently, it was only when the MSV setting material came out that they retconned it into a shell-firing weapon...

-- Mark

[Xenosynth]

Random but since I don't have access to the 08th MS Team OVA, and can only find one screen which... isn't really a good view, is this the same design as the Zaku Cannon from 08th MS team? It's from the 0081 Battlefield Record game, and I don't think I've seen that Zaku Cannon backpack in very many other places.

[toysdream]

That's the same gun we see on the 08th MS Team version, but it's built into the standard Zaku Cannon backpack (which also has thrusters in this version). The one in 08th MS Team also has a huge backpack to support this gun, and that backpack/gun combo is the same one attached to the Dom Cannon.

-- Mark

[JEFFPIATT]

http://www.oocities.org/gundam_08th/MS-06K.html
here is the 08th ms team version witch lacks the legs from tha zaku cannon msv type

[AmuroNT1]

Unfortunately they've never shown the 08MST Zaku Cannon below the waist, so we have no idea what kind of legs it has.

[toysdream]

It's usually said that it doesn't have a lower body, but nobody's sure why. Is it a damaged unit, or some kind of weird kitbash? When we see it from the front in episode 3 of 08th MS Team, its chest seems really huge compared to a regular Zaku, so it could perhaps be cobbled together from assorted parts and not technically a mobile suit at all. It actually reminds me a bit of the Hildolfr from MS Igloo...

-- Mark

[Zeonista]

Anyway, it turns out that the reason the cannon looks so much like a beam weapon is because it was originally supposed to be. Tipped off by the Japanese Wikipedia, I checked the "Anime Graph Book" where the MS-06D, K, and M first appeared, and the description attached to Okawara's original drawing says it's armed with an anti-air beam cannon. Apparently, it was only when the MSV setting material came out that they retconned it into a shell-firing weapon...

Ah, what a comedown in the revision! I can understand it a little though, since in the original OYW story beam weapons were decisive battle weapons for MS. If the ZEF had been able to deploy 9 such units several times, it might have become a Two Year War.

On p. 58 of the Zeta Gundam Mechanical Edition Vol 1 (Newtype 100% series), the Zaku Cannon used by the EFSF and inspected by Sirocco is featured in lineart. The cannon and its backpack are clearly a beam weapon version. For easy comparison the GM cannon is on the other side of the page. The difference between that backpack and the Dom Cannon pack are very distinct!

[toysdream]

There are a few sources (like the Zeta Gundam Data Collections) which say that the Zeta version of the Zaku Cannon has a beam cannon. The nice thing about this new theory is that, in a nutshell, everybody gets to be right! There is a shell-firing cannon, which clearly has huge mass balance problems (judging from the bulk of the 08th MS Team version), and there's also a beam cannon that obviously doesn't.

Also, as per the MSV-R series, the California Base produced 24 sets of conversion parts for use with the regular Zaku, thus giving us the MS-06JK. These sets included a new shoulder shield, the 180mm cannon pack, and a 120mm gatling gun option. (Every JK type we've seen in the MSV-R art has the gatling gun, so no conflicts there.) So the one in 08th MS Team could also be a makeshift turret cobbled together from one of these conversion sets, making it literally a "Zaku Half Cannon"!

Based on the MG Zaku Cannon kit manual, it seems that the combat debut of the Zaku Cannon can now be narrowed down to late October of U.C. 0079, when the Federation Forces were making a series of attacks on the Zeon forces to divert them from Operation Odessa. Apparently the Zaku Cannon was first detected during one of these raids. That would be a month after the Guncannon's combat debut, and a month before Zeon began beam rifle production. We know that before Zeon began beam rifle production in late November, the Gelgoog was using a backpack beam cannon as a stopgap, so the timing actually seems perfect for a prototype beam cannon!

It's not clear exactly when episode 3 of 08th MS Team takes place, but it's somewhere between October 8 and October 25, so this would be before the appearance of the "real" Zaku Cannon. Perhaps it's left over from the failed early version...


On a tenuously related note: In the previous Vintage MS Specs thread, I'd put together a scaled comparison lineup of mobile suits with propellant tanks. Here's an update:

http://www.ultimatemark.com/gundam/imag ... arison.jpg

The main change here is that I incorporated the propellant tank capacity labels from the Master Grade MS-06R and MS-14B kits. These are listed in pounds, and the figures are way smaller than they should be, but I just realized that if you add a zero to the numbers they come out just right. Compare the 6.5-ton tanks on the EWAC Zack to those of the MS-06R-1A and MS-14B...

Also, based on these numbers, the MS-14B has 2.4 tons of propellant in its backpack tank. This suggests that the standard Gelgoog has a total of 14.9 tons of propellant - almost exactly equal to the Galbaldy Beta - and that the ReGelgu's extra tanks add exactly 20.0 tons of propellant.

-- Mark

[AmuroNT1]

It's usually said that it doesn't have a lower body, but nobody's sure why. Is it a damaged unit, or some kind of weird kitbash? When we see it from the front in episode 3 of 08th MS Team, its chest seems really huge compared to a regular Zaku, so it could perhaps be cobbled together from assorted parts and not technically a mobile suit at all. It actually reminds me a bit of the Hildolfr from MS Igloo...

-- Mark

Since one of the recurring elements in 08MST is that there aren't a lot of supplies to go around there, maybe the Zaku Cannon is just a salvaged unit that they turned into a gun emplacement? Heck, you could even say that's why it has the Dom Cannon's backpack - they slapped it onto a spare Zaku body, maybe beefing it up a little so it could support the extra weight.

And the whole thing with the 06K's cannon alternately being called a solid or beam weapon reminds me of the Mudrock, with a few rare sources (like some G Gen games) depicting its 300mm cannons as beam-firing. I believe the Zeonic Front novel stepped in and said that the original plan was for Mudrock to have beam cannons, but they couldn't work out a cooling system for it so they went with shell-slingers instead.

[toysdream]

Also, part of the logic of the Mudrock is to "cover" for the slow recharging of the beam rifle by switching to a backup weapon that doesn't drain the mobile suit's energy supply. That wouldn't work if the backup weapon was also a beam cannon! Same goes for the Full Armor Gundam and Heavy Gundam.

When it comes to the RX-78-6, the original profile text published with the M-MSV series should be pretty definitive, and I've just finished translating this and a bunch of other profiles from the old MS Encyclopedia. Here's the original profile...

This machine was redesigned in the later stages of the One Year War based on data obtained from the Gundam Unit 2. In order to maintain its firepower after the beam rifle ran out of energy and until it was recharged, this prototype was given reinforced fixed armament. The new grenade launchers added to its forearms can fire four rounds per arm, for a total of eight rounds. Two 300mm low-recoil cannons were installed on its shoulders, and its backpack was accordingly replaced with a larger type. Due to the installation of these cannons, its beam sabers were moved from the backpack to the variable thrusters on its legs, and a beam saber ejection system was adopted.

-- Mark

[AmuroNT1]

Interesting that the original G06 has its sabers in the leg armor, while Mudrock has them on racks parallel to the cannons.

Also, I don't suppose there are any images of the G06 or Mudrock's grenade launchers, are there? We know they exist, but I've never seen any lineart and they haven't been usable in any of its game appearances.

[balofo]

Also, I don't suppose there are any images of the G06 or Mudrock's grenade launchers, are there? We know they exist, but I've never seen any lineart and they haven't been usable in any of its game appearances.

That and all the missile bays and some arm options for the 7th Gundam(didn't even make into Katoki's redesign) don't have lineart AFAIK.

To this day I'm waiting for confirmation on what the Zaku III Custom Hide Bombs look like, I doubt they are the same as the Gyan(since the Crackers don't match the old ones used by the Zaku) so I just fanwank them to be just the same as the Hamma-Hamma's shield space mines...

[JEFFPIATT]

http://gundam.wikia.com/wiki/MS-06W_Worker_Zaku
the worker Zaku is really the unit that confuses me since it is classed as an ms-06 zaku II unit but it appers to use ms-05 zaku I parts like the zaku I head. it appers that the ms-o6 code can be applied reguardless on the worker units since the 08th ms team version of the zaku tank used an ms-05 torso but still had an zaku 2 model code.
http://gundam.wikia.com/wiki/MS-06V_Zaku_Tank

[toysdream]

Following up on the various types of cannon, here's a scaled comparison chart...

http://www.ultimatemark.com/gundam/imag ... arison.jpg

I think the standard Zaku Cannon armament could plausibly be interpreted as either a 180mm projectile weapon or a Gelgoog Cannon-style beam weapon. That muzzle is pretty weird for a projectile weapon, though!

Further to the right, we have the MS-06JK modeling the gatling gun option, and the Dom Cannon with its big old gun (the same one seen on 08th MS Team's Zaku Cannon). These weapons seem roughly equivalent in size and ammunition storage, so it's not hard to imagine them as being the two options included with the "Half Cannon" upgrade set. As Xenosynth pointed out, this is the same gun we see on the Zaku Cannon in the Gundam Senki U.C. 0081 game:

http://i.imgur.com/8NVQLme.png?1

And finally, we have the GM Cannon, whose shoulder-mounted rocket launcher is variously listed as either 240mm or 360mm. Since it's a rocket launcher, this would theoretically work more like a built-in bazooka than a tank cannon, but unlike most Gundam bazookas it doesn't have any vents for the rocket exhaust. So again, if you told me this was a 240mm shell-firing cannon, I'd find that just as plausible.

-- Mark

[AmuroNT1]

Not to derail the topic (I already kinda did that in Mark's other one, sorry. ), but is the missile launcher on the Dom Cannon supposed to be the same one that was in Zeonic Front on units like Royer's Gouf Custom?

[Ferrus_Manus]

http://gundam.wikia.com/wiki/MS-06W_Worker_Zaku
the worker Zaku is really the unit that confuses me since it is classed as an ms-06 zaku II unit but it appers to use ms-05 zaku I parts like the zaku I head. it appers that the ms-o6 code can be applied reguardless on the worker units since the 08th ms team version of the zaku tank used an ms-05 torso but still had an zaku 2 model code.
http://gundam.wikia.com/wiki/MS-06V_Zaku_Tank

I think the Zeon took what they had to construct the Zaku Tank and Worker Zaku. And the Zaku Tank is not a standard MS by any means. They were built at field maintenance bases, and not factories. And if they only had a Zaku I torso, they used it instead of a Zaku II torso. Beggars can't be choosers, I guess.