A traverse stop clamp is provided for restricting sweep of a machine gun mounted on a tripod. The stop clamp is installable on a traverse bar connecting to rear legs of the tripod, the traverse bar having an inverse U-shape cross-section that form edges at ends of the U-shape. The stop clamp includes an open ring member, a shift member, a handle, a spring pin and a locking nut. The open ring member has a C-shaped ring with an interrupted circumferential outer periphery and an inner periphery with channels for receiving the edges of the traverse bar. The outer periphery has first and second ring ends separated by an adjustable gap. The open ring member further includes first and second tabs disposed to extend radially outward from the first and second ends. These first and second tabs respectively have first and second through-holes. The shift member has a tang and a shaft at respectively first and second shifter ends. The receiver has a third through-hole, and the shaft has a threaded terminus. The tang and shaft pass respectively through the first and second through-holes. The handle has a lever and a clevis head with coaxial fourth through-holes. The head has a cam separating a lock clevis face and a release clevis face. The lock clevis face engages the tang in response to the lever being adjacent the outer periphery. The release clevis face engages the tang in response to pulling the lever away from the outer periphery. The handle pivots at the fourth-through-holes to widen the gap between the tabs. The spring pin passes through the fourth and third through-holes to connect the tang and the clevis head pivotably together. The threaded lock nut attaches to the threaded terminus to engage the second tab.