New to the game, so bare with me. For measureing the most accureate OAL on a non custom (hope to be soon) long range hunting rifle. 1. Take fire formed case and cut slits in the neck with drimel. 2. Seat the round I want to use (Berger 190gr for a 300 mag), in the case with slit and leave it long. 3. Carefully chamber round, and carefully extract the round. 4. Look for the marks left by the lands, and mesure them. 5. Then take the measurement from 4 and subtract what ever distance off of the lands you would like be. 6. Adjust the seating die to make said round 7. Then for record keeping purposes, us a bullet comparitor to meassure OAL of round from 6. Does this sound right, assuming it will fit into my magazine?