With those short bullets you may not be able to touch the lands or even get close and still have enough shank to hold it in the case. You can try the old split case neck trick. Take a case and full length size it. Cut a line down one side of the neck to the start of the shoulder. Clean up the burrs. Just start a bullet in the neck by hand and slip it into the chamber and close the bolt. Carefully remove the case and measure the COAL. The bullet will be pushed back into the case when the bullet ogive hits the lands. This measurement will be your to the lands measurement. Sierra bullets like to jump a ways. That 100 gr HP is a bomb and it likes to jump a looooog way. I have shot it in my sported Mauser 96 6.5x55 and I could not get within a mile of the lands. It has a free bore made to shoot the 156 gr RN bullet. I just seated the bullet .264, a calibers depth in the case and it shot lights out. I was running it 3200 fps and it would evaporate when it hit a ground hog and scatter pieces. Oh, you can pull the bullet out of the split neck case with your fingers and load it and shoot it or use the case with other bullets to find your COAL.
