I've checked Googlefu and rfc with very little results. Of the few that I've found,results were mixed. My 457 Varmint has a head space of .045. It's within the normal range. The ammo I shoot, RWS ss 40gr hp measures a rim thickness of .042. I've read that some reduced head space to their rim thickness and improved group size. Others it had no affect. Has anyone here altered theirs? What results did you get? I'll only be shooting the rws ss 40gr hp ammo. I know I would have to change if I went to other ammo. Thanks
