NF mounting and zeroing issues

[nwtnorthman]

I thought I'd throw this out there, cause I'm at my wit's end.

I got a nice new Tikka T3, and decided my take my NF SHV 4X20X56 scope off my Remington (it was mounted in a NF one-piece 20 MOA base). I purchased a DNZ one piece 20 MOA base in, mounted the NF scope and off I went to the range. Shooting very low and had to pretty much top out my elevation to get it zeroed. Since I didn't like that too much, I changed the one-piece base to a Warne 0 MOA base and rings for the Tikka, remounted the scope and used the laser boresighter to see where I was. POI is still extremely low, the revolution marker on the elevation turret of the scope is at 8. 8 full revolutions to get boresighted, leaving only 20 MOA of elevation remaining.
The DNZ mount had high rings, the Warne rings are in extra high to ensure clearance of the scope's 56mm objective.
Does anybody have any ideas why I've had to dial up so much? I spoke with Nightforce directly, they're going to escalate it to a manager because it doesn't make much sense to them either. I've ensured proper mounting, tried two different bases, ensure that the base isn't a 20 MOA in error, everything is level, and I'm pretty much feeling like tossing the whole rig into the river.
Any thoughts would be welcome.

 

[ALBERTA BOY]

That’s pretty tough! My first though was that the 20 moa base might have been installed backwards. Since you installed a 0 moa base, it looks like you’ve already eliminated the possibility.

You’ve replaced the base, the next thing I would do is swap the position of the front and rear rings. I’of they’re at fault, the problem will reveal itself this way and you’ll be hitting in the opposite direction. Failing that, try a different scope to troubleshoot or try the same scope on a different rifle. If none of those reveal the problem, I’d start looking at the rifle itself.

None of this should require range trips. If the adjustment is THAT far off, simply looking down the bore and then through the scope should reveal any discrepancies.