Went to the range today and sighted my new falcon scope in at 100 yard range, its mil mil scope, after sigting in at 100 yards i dialed in 3 mils up on the scope and only got around 2.5 mils up with the group, did the same on the windage and had the same problem, it seems to need around 1.3 to 1.4 mils on the turrets to hit one mil on the target, is this common with the falcon scopes, this is my first mil mil first focal plane scope, it always returns back to zero, but i expect it to give me what i ask it to, please help, and thanks in advance