Folks have been using spirit levels on front sights for decades. Once calibrated for how much angle the rifle cants for a given shift of the bubble to one side, it's easy to correct for wind.
US Navy Distinguished Marksman Badge 153
Former US Navy & Palma Rifle Team Member
NRA High Power Master & Long Range High Master
NRA Smallbore Prone Master
Last edited by Bart B.; July 13, 2013 at 05:33 AM.