The film correctly shows the way the historical Wild Bill carried his revolvers, butt-forward in a belt or sash without any holsters.
This was Novak's first theatrical film in several years. Then 44, she arrived on the set nervous and self-conscious. Bronson sensed her anxiety, and intentionally screwed up his lines in their first scene together to reduce her fear and bolster her confidence.
This monster movie was produced by Dino De Laurentiis who around the time of the mid-1970s in the wake of Jaws (1975) produced a number of these movies featuring wild beasts. These movies included King Kong (1976), Orca (1977) and The White Buffalo (1977).