For the 50th anniversary of Jim Leatherwood's legendary Automatic Ranging Trajectory (ART) scope, Hi-Lux introduces the redesigned ART M1000-PRO. The original Auto-Ranging Telescope (ARTel) was issued to US Army and Marine Corp servicemen over 40 years ago. Since then, Hi-Lux has refined and improved the ART system's general cam to compensate the bullet drop of virtually any caliber. The ART scope's integrated mount provides external adjustment through the Trajectory cam. Selecting the proper cam setting will effectively match your rifle's trajectory curve to the curve of the trajectory cam. There are two ways to automatically compensate for trajectory when using the ART scope:Framing known sized targets within the HR1 reticleDialing the Cam to a known distance To automatically range known sized targets, the shooter needs to frame the target within the reticle. In Auto/Ranging mode, adjust the cam until the known size target fits within the designated framing...