S1, E4: Wil Willis heads to Fort Sill, Oklahoma, the US Army's training ground for fire brigades to see the 428th Field Artillery Brigade launch 155 mm projectiles from the M77 Howitzer.

S1, E4: Wil Willis heads to Fort Sill, Oklahoma, the US Army's training ground for fire brigades to see the 428th Field Artillery Brigade launch 155 mm projectiles from the M77 Howitzer.