You know the restaurants are going to be packed for brunch. Take her to the range!
Make the trip about her. Let her do most of the shooting. Guide her is she needs guidance. Encourage her. Don't make her shoot what you think she should shoot. If she likes the .22LR rifle, let her shoot it a lot. If she likes the .44mag, let her.
--My mom died in 1994. I never got to take her to the range. Don't wait.