Currently, three variants of the Type 99 20mm cannon are implemented in WT.
Type 99 Mark 1
516RPM, 600m/s
Type 99 Mark 2
490RPM, 750m/s
Type 99 Mark 2 Model 5
750RPM, 750m/s
(All feature in-game performance)
Among these, the Type 99 Mark 2 combines Model 3 and Model 4 into a single designation without distinction, but historically they differ as follows:
Model 3
Drum magazine, 480 RPM, 750m/s
Model 4
Belt feed, 500 RPM, 750m/s
Furthermore, according to Wikipedia, a “High Rate of Fire Version” of the Model 4 existed, and mass production and deployment had begun by the time the war ended.
Model 4 “High Rate of Fire Version”
620RPM, 750m/s
Issue of this is that there isn’t any mention about different variants of mod 4 guns in manuals. Even A7M manual just says mod 4. So it looks like any plane with mod 4 could be equipped with mod 4 higher RPM
I tried to understand how to identify the mod 4 with higher fire rate and understood:
And we can see part of mod 4 and mod 4 kai (I will call it like that), the difference between them is having 2 protrusions on the end of mod 4 kai. After reading some data (don’t remember which one) I got a conclussion that this 2 parts are what make mod 4 kai from mod 4 and can be placed and deleted from gun without big changes.
Type 99 Mark 2 Mod 4 simple without parts on the end
It is so nice information!
Especially I like the part “It is an attachment type, requiring no modification to the gun body” which approve assumptions that it can be used on any plane with Type 99 Mark 2 Mod 4
The above contains the following descriptions regarding mod.4 (standard type, not “kai”):
Prototypes aimed for 580 rpm
Recoil force reached 1.5 tons, damaging the aircraft mount
Production models reduced this to 500 rpm
mod.5, with a muzzle velocity of 760 m/s and firing rate of 750 rpm, had a recoil force of 2.5 tons
At the time of the standard mod.4’s development, the A6M was likely the only aircraft capable of mounting the Mark 2 cannon.
This means that while the “mod.4 kai” could physically be mounted on any aircraft designed for the Mark 2 mod.4, it would be impractical without reinforced mounts.
The following is personal speculation:
The A6M, being structurally weak, would be fundamentally incapable of mounting it. However, models like the A6M5c and later, with reinforced wings, etc., might have a possibility.
Aircraft like the J2M, N1K2, and A7M2 were robustly designed from the start, so they should be fine.
The B7A2 also had a sturdy design capable of withstanding steep dives, so it should be fine.
