Earlier adoption of cannons by the Japanese ARMY Air Force?

While the Japanese Navy was quick to adopt cannons for the A6M Zero and their other aircraft, the Army stuck with heavy machine guns much longer on even their more modern planes, like the Ki-61. The Army did have a better 20mm cannon than the Navy's Type 99, the Ho-5. However, I can't find a source for when the Ho-5 was made. Can someone help me out on this?
 
Hre's a link about JAAF guns.
http://gunsight.jp/b/english/data/ja-gun-e.htm

Can also peruse through the japanese wiki article on Ho-5, it looks like it's called Type 2 which is 1942, but as far as i can see in entered service in 1943. The Ki-45 also had a 20mm cannon, Ho-3, but i don't know how suitable it is for single engined fighters.

But yeah at the very least you can get cannon armed Ki-44 just by adopting the same 20mm Oerlikon gun like the JNAF, preferably with at least 100 rpg. Same with Ki-61, speaking of which i also like the idea of Me-109 style armament, ie an axial 20mm gun with 150-200 rpg and two cowling guns (12,7mm Ho-103s). IJAAF actually imported 800 MG-151/20s from Germany in 1943 for later Ki-61s, but again i don't know how suitable is the Ho-5 as an axial gun.
 
Top