Hi,
regarding the armament hit probability so kill probability many dont seems to see that not only the armament is a factor!!
As long as a target fly strait or is very big and get attacked right from 6oc, a slow firing gun have exact the same hitprobability per ammoload like a fast firing gun, therfor i would tend to use cannons vs big targets(bombers), specialy cause the better penetration of the structure.
Interesting it get when the target roll/turn/dive/climb and if the attacker is forced to estimate a deflection.
MG´s in general tend to have a much longer time to shoot, therefor its good possible to adjust the aim while shooting, without to waste to much of the ammoload. Additionally many MG´s dont let a "open window" between each bullet, also this is very important, specialy while shooting with a high deflection.
Imho the Tempest, HurriIIc and F4U-1c only are extremely danagerus in the H2H area with extended ammo load. In the other areas, with normal ammo load, the pilot need to be much more carefully not to run out of ammo.
Time to shoot is a big aspect of the armament hitprobability and MG´s in general could carry much more ammo!
P47D could shoot 32sec.
F4U-1c 23sec.
Tempest only 11,5sec.
HurriIIc only 9sec.
SpitIXc 12sec.
Of course the F4U-1c, HurriIIc, Typhoon and Temp had a extremely good firepower and vs not or slow moving groundobjects and bombers this is very good. But what is the firepower worth, if the pilot dont have enough ammo to adjust a bad calculated lead(the F4U-1c is almost a exception here, but still have 30% less time to shoot that the P47)??
While shooting to a smal fighter from a perfect attacking position(short range, 6 oc, enemy fly strait) or if the pilot was able to calculate a perfect lead, even 2 x MG17 + MG151/15 was good enough, like Mr. Marsaille and Mr. Graf did proof in a very impressive way.
Therefor i think with increasing distance and attackingangle, but decreasing pilot skill, the need of more guns or faster shooting guns with big ammoload, NOT more powerfull guns, was needed! (vs Bombers of course more powerfull guns was better, while the .50cal still was effective vs fighters on common shooting ranges)
At the end of the war and after the war, the computed gunsights did improve the hitprobability much, cause the pilot as influence got almost deleted. Therefor the need of a very long time to shoot wasnt needed anymore, so a smal number of cannons probably would have been a big improvement, cause they was effective vs fighters, bombers and groundobjects, on a longer range(with the computed gunsights long range hits got much more likely) and they was more light.
Greetings,