I don't have a COAL gauge. So I did it what I feel is a somewhat useful way to find the lands. First off, it is a Savage 10-Tsr rifle. I'm using 143 ELDX. The bolt wouldn't close at 2.91". So I backed down to the max that the mag would allow and still cycle fairly well. My end result was 2.87" COAL. I have not shot it yet to see how it does there. The rifle shot .4" groups with a 2.82" COAL, so wanted to see if it would get better going closer to the lands. This seems much longer depth than what I hear from most. Am I wrong somewhere?