Hello Der Ami,

Thanks for the reply.

I have acquired a "clock-key" that fits the windage adjustment peg on the sight base. You can see this square peg near the front of the base below the scope.

I have corrected the group to be centered on the target. The rifle is now zeroed at 200 yards and ready for hunting.

I settled on "new" Speer 8mm bullets weighing 225g (.320 dia) using 39g of IMR4320. Velocity = 1900fps and 5-shot groups measure about 3" at 200 yards.