HH-60W Jolly Green II begins live-firing weapons testing on:
GAU-2 - a 7.62mm Gatling gun with a 3,000 rounds per minute fire rate.
GAU-18 - a .50 caliber legacy machine gun with a 650-800 round fire rate.
GAU-21 - a .50 caliber newly-designed machine gun with a 950-1100 round fire rate.
13 photos here: https://www.afmc.af.mil/News/Article...-fire-testing/