Lee Kay: (300yds) 6000 W 2100 South, SLC
PMAA: (800yds) ?I 80 E. Exit 134 1 Highway 65 S Salt Lake City
North Springs: (1680yds+) 5245 S 8000 W, Price, UT
West Desert north of I-80, west of Stansbury
West Desert out past 5-mile Pass on 73
Best thing to do is hook up with a local Arfcommer who has all the areas worked out, where to go, and ride with them.
I prefer North Springs, but it's a 2:15hr drive from SLC. Considering set-up and break-down time for steel targets, North Springs is very appealing, as they have all the steel set up already and more of it than you can shoot in a week if you shot day/night (I've tried.)
I use Lee Kay for load development since you can ladder test at 300yds.
PMAA is a short drive up I-80 just outside SLC where you can shoot steel out to 800yds, with paper targets out to 100yds.