What is the highest muzzle velocity of a gun on any fighter aircraft? I'm looking for the greatest muzzle velocity of a gun on any fighter aircraft.

I looked up the GAU-8 Avenger from the A10 Warthog first. Its muzzle velocity is 1,070 m/s, which is pretty darn high (almost 3 times the speed of sound). Are there any faster bullets out there from an aircraft gun?

Note: Don't really care about the firing rate (rounds per minute), or bullet caliber. All I'm looking for is highest muzzle velocity.
The muzzle velocity of guns is based on multiple factors and generally sees a wide range. Most importantly how the bullet is loaded (gun powder wise) and what mass the bullet is. For example the P-51 mustang carried 6 50 caliber BMG's (M-2). Which (although not available at the time) is capable of accepting the Caliber .50, Saboted Light Armor Penetrator, M903 round which has a quoted muzzle velocity of 4,000 ft/s (1,219 m/s). It should also be noted that the base muzzle velocity of an M2 is 2,910 ft/s (890 m/s) for M33 ball round. So it really depends what round you are loading in.

The F-35 Joint Strike Fighter has the GAU-22 Gatling Gun which with the TP HEI ammunition has a quoted muzzle velocity of 3,560 feet (1,085m) per second (15 m/s faster than the GAU-8 on the warthog). 


(Not sure about you guys but I often test my gatling guns with my multi-meter...)
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