There is alot you can do without any range, but of course actual distance shooting is the best form of practice. Have you developed a mental program? This is a mental checklist of things you need to do before shooting, for example:
1. Know course of fire/shooting solution:
a. Locate targets and range using rangefinder, reticle, or provided distances
b. Examine wind clues and estimate in data book
c. Write this down in data book (order of shots, distances, elev/windage adjustments) or develop very good memory skills
2. Come up with initial plan for positions: off barricade, under log, whatever -- have this understood in advance and practice if allowed
3. Preload magazines for expected course of fire, have a couple backups ready just in case
4. Set sling for position needed
5. Remove scope caps
6. Dial first elev/wind settings
7. Take position and scope all targets again (if possible) to ensure you can find them quickly under the clock
8. Position rear bag
9. Execute the shooting solution
This is just an example, you need to develop your own checklist which may include additional steps if you have other equipment, such as tripods, range finders, etc. You should run through this mental checklist before firing, even dry firing at home. Get in the habit of running through it (with imaginary data if at home). Actually do each step that you can -- load mags (dummies at home), removing scope covers, dialing, etc. so that it becomes a smooth fluid process. Practice until you get to the point where you intuitively feel "something is missing" if you have forgotten a step.
