Season 5

After Red Jacket looses a lucrative contract, Will and Joe have a heart to heart about RJF's future. Will attempts to fit a 25mm Hotchkiss canon inside a pick up truck. Joe prototypes a flying drone, to fire remotely. Will is hand-delivered dreadful news.

A snowmobile is fitted with machine guns; Charlie works on a rare Japanese rifle.

Will is commissioned to make a triple-barrel shotgun.

Joe shows Will the new building; a customer brings a World War II 75mm Scorpion Tank to the shop, and the team quickly learns their new project may lead to some unexpected trouble; Steph and Charlie work on a small revolver.

Joe tries to convince Will to make his building Red Jacket's new home; Will must attach a Mac 11 machine pistol to a Saiga-12 shotgun; Kris snaps; Will learns about the AK-47 deal.

Mounting a long-range rifle to a vehicle; Will wants to debut a prototype, but Joe thinks using a different model makes more sense.

Will senses danger in the way a rare, water-cooled, 50 cal Browning machine gun is running. He steps in to keep the shooter safe, by rebuilding the powerful gun. Charlie defies Will by taking on a friendly bet. Will gives Joe an ultimatum.

Will faces some big challenges as he chooses Red Jacket's new home and works on the 155mm Russian D20, which is the largest civilian owned gun in the world; Kris sustains an injury; Charlie works on a suppressor for a very fast gun.

Red Jacket's new home has been selected, and Will and the crew are in the middle of moving when Will is asked to mount a Hispano-Suiza to the sidecar of a motorcycle; the RJF crew works on a weapon that shoots suppressed darts.