Hello
trying to sight in my 7mm remington magmum with new nikon 6.5 X 20 scope had it bore sighted shot at 100 yards took 46 turns of elevation at 1/8 incrermnets to get it just on the paper at 100 yards after 46 turns down was above center by 10 inches at 100 yards. However 30 yards it was hitting 1 inch above center which dose not make any sense was shooting winchester 150gr ballistic silver tips need to gety it sighted in quick but any out of ideas? could the ammo be causing such a varation really makes no sense any body got any ideas ?


thansk

al600 ,

46 Turns ? Is that 46 complete revolutions of the adjustment knob? I wouldn't think it would have that much adjustment. guess I'll just set back and learn.

First thing I would do is to check all action and scope screws for tight. then check the barrel for clearance at the forend. I prefer a floated barrel.

If you are 1" high at 30 yards and 10" high at 100 yards I'd say that something is wrong with your mount.

al600,

Ran your numbers for the 30 yard and 100 yard point of impact and they're not that far off. I don't have the particulars of your rifle, such as the height of the scope centerline above the bore, which makes a difference for your zero. But, with 1" high at 30 yards it calculated as 5.7" high at 100 yds. These short range zero points should be used as a check or emergency field zero point rather than zeroing for your final sight-in. Also the short range zero has to be dead on or you will have a lot of error out at 100 yds and past.

Reccomend you continue on and zero at your 100 yd point and then check where you are hitting at 30 yds. If you don't have enough adjustment left to do the zero, then that is another problem to solve.

Al,
What kind of base and rings do you have, standard base with adjustment screws for windage or a Weaver type with no adjustment? Did you check the base to make sure it was tight and the screws did not bottom out before the base became tight? You have the right base and if a two piece, the front and rear are not reversed.

Do you know how to make shim material from a beverage can? With scissors cut the top and bottom off, then cut from top to bottom, you now have a roll of shim material.

Remove the base screws and blue locktite them. If you have a standard base, center the scope's adjustment knobs, then turn the left windage screw on the base out 1/4 turn and the right screw in 1/4 turn, tighten both base windage screws.

Center the elevation knob. Cut and place three shims stacked under the front of the base then retighten the base screws. If you want to use the shims in the rings, that will also work. Cut shims for the rings about 2/3 the width of the opening and about 1/2 the width of the ring so the shims are hidden when installed. I do both, base and ring shims and prefer the shims in the rings for range insertion. Now boresight the scope using a small object at 150 or so yards with the rifle locked in place. Center the object in the bore first, then turn the crosshairs to the object. I like to use a 90 degree angle, like the corner of a window or corner of a sign, paper, etc. The centered verticle and horizontal lines follow through for the scope cross hairs.
Ed

Look at your mount. The scope rail has notches in it. The screws that clamp the mount to the rail have to be in those notches.