Watched a public domain gun camera video of an A10 gun attack a while back. I estimate the angle to the ground was 60 degrees. The rotary cannon made a bit longer than one half second burst. The projectiles hit about six seconds later. At 3.000 feet per second plus, slant range was about 3.4 miles, 5.5 km, altitude about 9,000 feet above ground level. Impacts were in a zone 100 m deep and 50 m wide and very evenly dispersed.
Very exotic gun sight.
I heard that, for enemies on the ground, they don’t hear noise of the plane approaching before they are hit. An ultimate silent killer.