Why 20mm aerial cannon does the damage

[old man emu]

 

[willedoo]

That was a big imbalance in armament in the Korean war between the F-86 Sabre and the MiG-15. The MiG's 2x23mm and 1x37mm autocannons didn't provide very accurate gunnery, but very few Sabres survived a single round hitting them. The damage done would usually take out something vital. On the other hand, a lot of MiGs made it back to base with many .50 Cal. holes and were repaired and flying again in a day or two.

 

With the different trajectories of the 23mm and 37mm rounds, some Sabre pilots told how they found themselves with one lot of tracer going overhead and the other passing underneath and none hitting them.

[willedoo]

Being a collector, I once bought a couple of Soviet empty aircraft shells on evilbay. One was a 23mm and the other a WW2 20mm. I never got to see them as I didn't think to get a state police authority to possess them and federal customs destroyed them. Federally, it's illegal to import any ammunition component of .50 Calibre or larger unless it's trench art or part thereof.

[old man emu]

I think that the point of the video was to explain why the Germans used an exploding bullet. It seems that the idea is to cause widespread damage from a single point of contact, as opposed to firing a multiple small items which spread as soon as they left the barrel - like birdshot, or grapeshot. The use of a 20 mm calibre simply allowed for a bigger projectile, which meant it needed a bigger propulsive force.

[willedoo]

A lot of autocannons have multiple different rounds in the same belt. Penetrating rounds followed by explosive rounds. And the tracer - is it every five rounds or so?

[willedoo]

The wingman of the Soviet pilot who shot down W.O. Ron Guthrie in Korea provided an account of it. Apparently the Meteor copped a lot of rounds, probably both 23mm and 37mm. When the wingman  approached, the MiG pilot doing the shooting thought he was a Sabre, so he did a dive and bolt back to base. The wingman followed Ron Guthrie for a while and was impressed by his efforts to control the aircraft with bits falling off it everywhere. Eventually when it became too hard to control, Guthrie egressed, performing the world's first combat ejection with an ejection seat. I think the Meteor was shot from the rear, so maybe less vitals were exposed as compared to an oblique shot. The Meteor is a fairly tough old bird from what I've seen of them).

[onetrack]

If you ever go to the old 1934 Qantas Hangar Museum in Darwin, you can find Japanese 20mm cannon shell holes in the uprights of the hangar. However, the Zeros 20mm cannon was pretty much a copy of a 20mm Oerlikon, and it didn't use explosive projectiles like the German 20mm, and the muzzle velocity of the Japanese cannon was relatively low. I still wouldn't have liked to be on the receiving end of one of those cannons.

[Old Koreelah]

12 hours ago, willedoo said:

A lot of autocannons have multiple different rounds in the same belt. Penetrating rounds followed by explosive rounds. And the tracer - is it every five rounds or so?

There was some interesting research that indicated aerial gunnery without tracer rounds was more effective.

Apparently the lighter tracer projectiles travelled significantly lower than the full-weight main ammo, causing aiming errors.