Originally Posted by Jon
Different issues ones power fluctuation the others zero shift and common knowledge.
Spot on John,the problem with my Ar5s is definately power fluctuation associated with decreasing temps.
As a matter of interest I put my Ar4 over the chrono and starting off from a temp of 18 deg. C it registered an average of 774 fps.Left it out side ,temp dropped to minus 2 deg and recorded a average 770 fps. A lot better than the thirty odd I was getting on the Ar5s