It's a necro, but not a bad necro.
Not a sub gun, but I've put at least 30,000 rounds through a 20mm Vulcan in an F-15 as a youngster. 6,000 RPM. It's hydraulically driven, electrically primed. There is no individual banging... it's a horrendous rrrrriiiiiipppppppppppppp that sounds like godzilla is roaring just outside the cockpit.
There are some guns that do better than 6,000 RPM, but not many. After my Eagle tour, I instructed in a jet called the AT-38B. It mounted a gun pod called the SUU-11 on the centerline to teach basic strafe.
Looks like this, but mounts a standard 7.62 minigun...
The funny thing - we HATED the SUU-11. After the Vulcan, it was like shooting a Lorcin. Almost no tactile/visual feedback. The biggest problem was that the ground target used acoustics to determine a hit, and it needed a supersonic bullet to score. This caused the students to fly in WAY too close, dangerously close, to get those precious hits.
I like fast subguns, which is why I like the Uzi series, MACs too, because both are stupid easy to alter the rate of fire with buffers and/or springs. Most people who shoot my stock full-sized Uzi find it "choppy" due to the slow ROF. Jacked up a bit is where most seem to like it, call it 800 to 900 RPM.
