So the day turned out as expected - 14 degrees, sunny, calm....ideal day to try the challenge. Warmed up with my son's .223 bolt and tried the .5 MOA precision rifle challenge...didn't make it but may have gotten the 0.75 MOA licked

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Then I break out the M305 with the BF tension reduced to help with the stringing that has been bothering me lately. 10 rounds of Norc to re-zero the scope and what do you know...the Norc shoots pretty nice. Now I load up some more hand loads and shoot a few promising groups but by target 3 I always seem to be getting one round opening the group to 2 or 2.5 MOA...crap! Also still getting stringing just not as bad.
Out with the wrench and BF tension reduced by 60 degrees more (~1/6th of a turn). Rifle shoots better...more consistent...promising as long as I keep the rate of fire low and let the barrel cool. I shoot two more attempts (5 targets each) with the second being close to passing the challenge. I think I can get this next time but I better start looking for more bullets

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Had fun and brass is tumbling as I write.
Groups: 1.26", 1.97", 1.41", 1.57" and 1.41"