Twist Rate and Low Temps.
Recent .308 shooting results (168gr. Fed GM & 144 gr. quality Mil.) have been less than consistent. The variables from better days include: slicker shooting surfaces (HSRC on tarps on hardpack/icy snow), wandering buttstock-to-shoulder-pocket interface (many layers of clothing), and temps 40-80 degrees lower than this past fall and summer (its been 0-20 degrees the past 2 months).
Leaving out the first two variables, is anyone else getting huge groups when shooting at these low temps?
Do I need a different stick with a different twist rate for winter shooting?