I have been thinking on collecting the parts for a 338 caliber build. Would the edge based off the ultra mag case be better to work off of than the lapua with the bolt face opened up to allow the brass to fit? Single shot heavy gun, is what I am thinking. Don't really care how heavy just want a 300 smk hitting what I am aiming at. Realistic range would be 800 yards or less around this area. Have not really figured out what stock that I would want for the project, just that it would be set up for single shot. Thanks oldfamily.