Never had this problem before.

Boresight ended up being 10 MOA below the center of the scopes adjustment range. Boresight windage is nearly dead center of the scopes adjustment range. I will be sure to note where my POI is when I sight in tomorrow.
 
If I have enough down adjustment once zeroed tomorrow. I will most likely order a 30 MOA base. Any recommendations on a brand for a 30 MOA base? I have a Weaver and an EGW base now. I prefer the feel of the Weaver. It is heavier and feels as though it is better quality.
 
Either that or buy some .010" shims. I hate the thought of shimming a base though. Just feels like a one piece base would be better.
 
kilotanker22 said:
If I have enough down adjustment once zeroed tomorrow. I will most likely order a 30 MOA base. Any recommendations on a brand for a 30 MOA base? I have a Weaver and an EGW base now. I prefer the feel of the Weaver. It is heavier and feels as though it is better quality.
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Unless you got a lemon, the EGW is better quality.
You could use Burris Signature rings and get the extra 10 you need
 
kilotanker22 said:
Boresight ended up being 10 MOA below the center of the scopes adjustment range. Boresight windage is nearly dead center of the scopes adjustment range. I will be sure to note where my POI is when I sight in tomorrow.
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Is that the mid point of each knob's range of clicks?
 
Question for you Bart. On my rifles that I know are going to be shot past 200 yds and accuracy is a premium--I make a point of ensuring the base and rings are leveled, lapped and trued so that they are all in "sync" and then true the reticle of the scope to the level of the receiver. Wouldn't you need to do that to ensure accuracy of the other techniques mentioned here? I have a collimator but don't like the fact that it's not adjustable in height relative to the bore and scope center (I've searched the Internet and can't find one that is and that is not also a simple magnetic face). Also tough to use on muzzles with devices.
 
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All the preliminary stuff you're doing is good.

Don't be concerned about the scope and collimator axes height above bore axis; doesn't matter. Tell me your collimator make and model and I'll explain why if I can find a copy of its instructions.

Read the last paragraph in post #13 on this thread. Let me know if you don't understand it.
 
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Don't be concerned about the scope and collimator axes height above bore axis; doesn't matter. Tell me your collimator make and model and I'll explain why.
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I think I already know the answer to that--it's a BSA with arbors and the glass on it is pretty crappy--though to it's credit the 1 to 4" grid @ 100 yds does match exactly to the MOA clicks on my loopy. The problem is when the scope is mounted to a canted 20 MOA rail, the grid shifts to the upper half of the field of view, so you can't really measure much of the elevation of the scope to the grid before your dial up drops below the grid.
 
Read the last paragraph in post #13 on this thread. Let me know if you don't understand it.
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I may have found the issue. When I mounted the scope, I must have inadvertently slid the scope back on the rifle. I normally mount my front ring edge about an eighth of an inch from where the tube begins to transition into the Objective. I noticed thee edge of the front ring was right on that datum line. I can not be 100% certain that the edge of the ring being on that datum line did not can't the scope up slightly at the front. It couldn't have been more than a couple thousandths of an inch I don't think. I don't think that it would cause a 60 minute of angle or so change. A change that large would be easily seen by someone looking for it.
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@Bart--perhaps I don't understand that correctly--I thought I responded to that in the next post I did. My take on that is putting a pressure point on the juncture of the tube and objective bell not only most likely will result in an asymmetry on the tube body of the scope--but can easily damage the internal mechanisms of the scope if there is enough torque provided by the rings. I ruined a scope to prove it.;)
 
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kilotanker22 said:
Yes, the windage is nearly exact and the elevation is 10MOA below the scope's center of adjustment on the turrets.
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The scope's line of sight axis is typically not on the outer tube's axis when those knobs are midpoint in their mechanical limits.

With the adjustments so set, do the 2 V block test to see how much the reticle circles around. Change the adjustments to where the reticle center stays at one place as the scope's spun around.
 
There's typically nothing near the main tubes junction to the slope on the objective bell that a couple thousandths outer tube dimension will change.
 
There's nothing near the main tubes junction to the slope on the objective bell that a couple thousandths dimension will change.
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OK--but if the entire scope body is under asymmetric pressure--can that not also affect other parts of the scope even if it is not in direct proximity of the scope ring "pressure point.?" Sorta like bending a stick between your hands--it may not necessarily break at your hand.
 
At the range now. Just fired the first shots since setting it all up again.

From boresight, windage was 4.25 MOA to the right. Elevation from boresight was dead on at 100 yards. Did not even need to adjust the elevation.
 
Got a perfect zero now with the ammo I am shooting now. I am burning up some Winchester range OTM ammo for brass. For a dead on zero at 100 yards from boresight I had to adjust 4.25 MOA left and .75 MOA down.
 
stagpanther said:
This is on the 20 MOA base? How much dial up elevation do you have (assuming 100 yd zero)?
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Yes, 20 MOA base and 100 yard zero. With this ammunition I have 41.75 MOA of Up adjustment. It would be really nice if I can find a 30 or 35 MOA base for this rifle. A 35 MOA base should give me around 57 MOA of up adjustment. And hopefully leave me just enough down adjustment to zero at 100 yards
 
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