Karnak is correct, I think. The AH G6 - which once did have the 30mm option - had its armament limited when we got the G14, so that the G6 would be flown in its typical 1943 form. This isn't so important in the MAs (but in the MAs you can fly K4 if you want), but it is very important in scenarios and special events and the AvA.
- oldman
There were very few Bf 109 G-6 with 3cm MK 108s in 1943 - some general info:
The Bf 109 G-6/U4 was a sub-series of the G-6 that was fitted with a 3cm MK 108 as centrally mounted weapon instead of the regular 2cm MG151/20. It was built by WNF, the planned production figure for 1943 being 800, or 810 according to another official source, beginning in May 1943 with the delivery of the first two aircraft. The actual production figure was considerably lower, in fact only 181 Bf 109 G-6/U4 being delivered until the end of 1943.
E-Stelle Tarnewitz was given the task to install and assess the MK 108 in the Bf 109 G-6, beginning in June 1943. They handled two pre-series aircraft, the first of 27 aircraft, the second of almost the same number of aircraft. The first deliveries began in the second half of July 1943, the 27 aircraft of the first pre-series being delivered to front line units until August 22nd, 1943 with the second pre-series aircraft being completely delivered until October 23rd, 1943.
In the Tarnewitz report for 21.7.43 with the title "Einbau und Funktionsüberprüfung der MK 108 in den ersten 30 Flugzeugen Bf 109 G6/U4" (Installation and functional testing of the MK 108 in the first 30 Bf 109 G6/U4s) gives an overview of the testing. Originally to they were simply to install the MK 108s in the aircraft, and then to give them a series of simple functional test.
The implementation of this simple plan would consist of the following: The aircraft were accepted minus the weapons, which I assume meant only the MK 108, rather than also the MG 131s. The weapons came from the final production line at DWM-Posen. The associated units for remote firing of the weapon came from Rheinmetall-Borsig, Berlin-Tagel and its sub-contractors. Anticipated was a short firing of the weapon on the firing stand, then a short firing of the installed weapon on the ground, and finally a short firing of the installed weapon in the air. But, in the rush to make the MK 108 operational it had not undergone the complete testing as specified by GL/C-E6.
Results: The 9 MK 108s delivered at the end of May 1943 had so many problems on the firing stand that installing them in aircraft was out of the question. In mid-June 1943, 24 improved MK 108s were delivered. They worked well enough that one was installed in an aircraft for testing. But, there were numerous problems with the installation that required extensive firing on the firing stand. The report then listed 8 major problems encountered. It also mentions that the training ammunition supplied by DWM had a different fuse cap than the Rheinemetall training ammunition with the result that 3 cannon were destroyed by the exploding cartridge casings.
In the end, everything was fixed up; and at the date of the report (21 July 1943), of the original 30 aircraft, 10 were still at Tarnewitz, and the others had been sent on to Schwerin or to Lärz.
So, according to the wording of the report, it would appear that the 30 aircraft mentioned were, in fact, accepted by Tarnewitz as genuine production G6/U4s rather than any other modified aircraft. The factory of origin of these aircraft is never mentioned, nor were any aircraft W.Nrs.
We can with good reason assume that the aircraft fitted with MK 108 at Tarnewitz - 1st and 2nd pre-series - were in fact the first Bf 109 G-6/U4 to roll off the assembly lines at WNF albeit minus their MK 108, and that it was at E-Stelle Tarnewitz, where these newly developed weapons were to be added to the aircraft. This is born out by the one WerkNr. that is mentioned in one of the weekly reports, which refers to a Bf 109 G-6 that was definitely built at WNF. Only after the more or less successful elimination of the many faults of the early MK 108 with the completion of the 2nd pre-series aircraft at Tarnewitz was it possible, to install the weapons already on the assembly line at WNF and deliver the complete aircraft as Bf 109 G-6/U4, which seems to have started with approximately the 60th aircraft to be completed.
Source - George Hopp / Dr. Jochen Prien
