I still do it the old school way. Shoot and clean after every shot, for 10 shots. Then shoot and clean after 3 shots, for 3-three shot groups. Then shoot and clean after 5 shots, for 2-five shot groups. You should be pretty good by then.
Use a good bore guide, Butch's Bore Shine, plenty of bronze brushes, and hose the bronze brush out with brake cleaner after every time you're done running it thru the bore.
Be patient, it'll pay off in the long run.
Thank you for the tips yukonal. Can you recommend a bore guide for Tikka T3?