M61 20mm VS GAU-8 30mm Gatling cannon test fire

When it comes to aircraft-mounted firepower, few weapons inspire as much awe as the M61 Vulcan and the GAU-8 Avenger. Both are Gatling-style rotary cannons, and both deliver devastating rates of fire. Both were also designed for very different types of combat. A test fire comparison between these two giants highlights just how differently they approach the problem of destroying targets.

The M61 Vulcan is a six-barreled, electrically fired 20 mm rotary cannon driven by hydraulic or pneumatic power. Capable of firing up to 6,000 rounds per minute, it overwhelms targets with sheer volume of fire. Compact and relatively lightweight for its power, the M61 has been the standard cannon for United States fighter aircraft for over half a century. It is arming jets such as the F-15, F-16, and F/A-18.

Originally produced by General Electric, the M61 is now manufactured by General Dynamics. Its role is clear air-to-air combat and strafing runs, where accuracy, reaction speed, and sustained fire are critical.

The GAU 8 A Avenger is a seven barrel, 30 mm cannon built around a single mission of destroying armored targets. Hydraulically driven and famously mounted in the A-10 Thunderbolt II, the GAU-8 fires massive rounds capable of tearing through tanks and hardened vehicles.

Its sound and recoil are legendary, and in many ways, the aircraft itself was designed around the gun. Beyond the A-10, the GAU-8 also serves as the core weapon in the Goalkeeper CIWS, defending ships from incoming missiles, aircraft, and fast-moving surface threats.

In a test fire, the difference between the two cannons is immediate. The M61 produces a dense, continuous stream of fire that saturates the target area. Thus, making it ideal for fast-moving aerial engagements and precision strafing. The GAU 8, by contrast, fires heavier and slower rounds with enormous kinetic energy, each impact delivering destructive force capable of shredding armor.

The M61 Vulcan represents speed, volume, and precision in air combat, while the GAU 8 Avenger embodies raw power and survivability on the battlefield. One was designed to dominate the skies, the other to destroy anything unfortunate enough to be caught on the ground. Together, they remain two of the most iconic cannons ever mounted on military aircraft.