There is a (magic) B-17 flying along at 560 mph. The tail gunner is out of
..50 caliber ammo. He sees a Messerschmitt ME-109 crossing behind the B-17,
50 yards away.

He pulls out his trusty .45 Colt auto (muzzle velocity 820 fps) and fires at
the Hun when the ME-109 is directly behind the B-17. He leads the
Messerschmitt by exactly enough to hit the pilot (if he were firing from a
fixed position).

Does the bullet exit the muzzle and fall directly to earth?

Rich "Scratching my head" S.