Texas reader Lannie Dietle suggests dialing a 7/8thsx14x3-inch hexhead bolt into your reloading press to facilitate determining desired seating depth.
"Ordinarily," says Dietle, "this adjustment is a trial-and-error process, performed with the use of the seating die. The disadvantage of using the seating die is inherent in the fact that the operation can't be observed. One must proceed in small increments, checking constantly, until the proper seating depth is discovered.
"Using the 7/8ths bolt, instead of the die, one can see both the case and the bullet during the entire operation. All you have to do is press the bullet up against the tip of the bolt until the case mouth is properly aligned with the cannelure. It is then an easy matter to adjust the seating die by lowering the seating plug until it contacts the correctly-seated bullet. Subsequent seating is performed using the die."