Bustful of Dollars (2005)

A bored pornographer suddenly decides to make the grandest Western sex film of all time, but suddenly realizes that going from shooting hot chicks performing anal-creampies, ass-to-mouth tricks and cum-swapping to big time movie production is no easy matter, especially when faced with a psychotic producer and porn actresses who can't string three words in a line, but boy, they can sure take it up the ass! It adds new meaning to the concept of a shootout!