McGill's pistol, in almost all of the episodes, is a Smith & Wesson 39. The 39 was designed in hopes of being a replacement for the U.S. Army's Colt 1911 during Service Pistol Trials held in 1954. The S&W 39 is a 9mm double action semi-automatic, while the Colt 1911 is a .45 single action semi-automatic. While the Army decided to stick with the Colt, some U.S. Special Forces in the Vietnam War carried the S&W 39. So conceivably McGill may have trained with the weapon and been issued one by "American Intelligence" before he was scapegoated out.
Richard Bradford didn't fully enjoy his time making the series. He disliked working with one or two of the directors and his acting style caused some bemusement on set for cast and crew.
McGill's car of preference is the Hillman Imp, of which he drives several variants across the series. Unused to handling manual cars, Richard Bradford had to be taught; generally, however, he was usually doubled for location shoots involving the vehicle as was fairly common practice for ITC productions..
The series was originally titled McGill.