[TRC Subaru]

Originally Posted by winny

RoF is important but not that important..
It's all about how much weight/HE you can get into a target.

To work it out properly you need projectile weight, % of HE in it and RoF then you could see what the difference would be for a 2-3 second burst..

The Russian projectile weighs 95 grams and is 6% HE.
The British projectile weighs 130 grams and is 8% HE
The German projectile weighs 92 grams and is 22% HE

Russian RoF = 13 RPS = 74g HE per second. (shVAK 20mm)
British RoF = 10 RPS = 104g HE per second. (Hispano MKII)
German RoF = 8 RPS = 161g HE per second. (MG-FF with HE rounds)

Then x that by the number of guns...

(this is ignoring the fact that the spitfire had MG's too)
Muzzle velocity isn't that important (although it does have a significant effect on accuracy).

Great analysis Winny, you clearly are knowledgeable of the subject of ballistics and I agree with your findings, M+V=D, (Mass + Velocity = Destruction…lol)

This formula I believe works very well if you are hitting a stationary object with all the projectiles, but when a moving plane is trying to hit another moving plane, you are often most likely to get a “sweeping” firing line where all the projectiles are not hitting, so with the faster firing gun (la-7), you will get more “hits”. Yes, the gun with higher mass has more “hitting power” but I believe you have enough destructive power with the La-7’s 95 gram projectile and when taking down a plane you need to get a hit in a “critical spot”, motor, fuel tank, etc. so with a higher rate of fire you have a greater chance of hitting a “critical spot” and taking down the plane. In other words, lets just say you have a gun with a 500 gram projectile and only 2 rps as apposed to a gun with a 50 gram projectile and 20 rps, both have the same theoretical destructive power but in a “sweeping fire path” the larger round may miss completely and the lighter round may land several hits, possibly hitting a critical spot and taking down the plane.

Same theory is why a 9mm full auto UZI is more valued in a fire fight then a 44 magnum six-gun. Bigger isn’t always better…

I’m not taking into account what armor the enemy plane has and several other factors, this is just my theory as an engineer, and I’m curious if this made a difference in actual combat, and if “More really is Better”