Ricocheting round knocks off shooter's earmuffs - video

[Saltfever]

Hmmm . . . do the 5th grade math. 2800 FPS is .000357 seconds per foot. The round trip (100 yards each way) is 600 feet. Total round-trip time should be about 0.214 seconds. Put an old stop watch (or your fancy I phone timer) to the video. I get 1.6 seconds from muzzle blast to return impact! Even accounting for my bad timing reflexes or a non-real-time video there is a 700% reality error! What am I missing!