Well, doing the math, a BB at 200 MPH is moving at 1,056,000 feet per second which comes out to a muzzle velocity of 293.33333 feet per second. The old lever action Daisy BB guns (long barrel) could spit out about 275 feet per second and the CO2 powered pellet long barrels could spit out up to 600 feet per second muzzle velocity. So yeah, the 200 mph BB part is likely true.
Is he using a magnetic sword and a crack shot sniper? Very interesting! 8-)