Re-checking my zero

I've shifted my scope back on my 17 MOA rail - as far back as it can go without blocking the bolt.

That seems to have produced a 2 MOA change in zero point.

So off the the 100 yard range to confirm the change ahead of a end of season shoot tomorrow.
A cold blustery wind blowing across the range.

Confirmed a +2 MOA change of zero.
The 300 yard zero wiil be at +2 MOA until I adjust the scope. I can allow for that.

Shot two groups - a 10 shot group on the right and a 6 shot group on the left.
The right group is about 3/4 MOA wide by 1 MOA high, the left group about 3/4 MOA wide by 1/2 MOA high.

Rifle: Barnard 308 action, 32" 1:10 True-Flite barrel.
155gr Lapua Scenar projectile in Lapua Palma cases with 44.5 gr Varget.
Federal Premium Match small rifle primers.

Attachment 69097

I wouldn't be tooo disappointed with either of those groups

I could live with that

Yes but you dont stay that good by living with it do you ?

I would come up another 1/4 or 1/8 moa and that will give you an edge over a number of 10 shot strings. Keep a critical eye on your first half dozen competition shots anyway.

It looks as if you were picking the wind ? A 308 would drift more than that on wind variations even at 100yd.

What do you think is the cause of the 2 moa change ? Is the rail not exactly 17 moa all the way or is there a speck of dirt in the surfaces somewhere, switched ring components or something ? I guess you re wondering about that sort of thing . I once found my airgun shot 3 moa high wih torch clamped on top of the scope so perhaps its just differences in angular inertia due to moving a signiicant component of the hardware. Of course your body position will have changed too.

It seems shifting the scope back gives you a good position. How does grouping compare to the previous set up ?


However its good shooting and a great basis for next season.

I would be happy with that alright