300 win mag 300 yd zero troubles

[moparman]

Weather was decent today so i tried to re zero my 300 wm at 300yds today with a new scope and base. The rifle is a round front flat rear savage 110 action with a 30 inch bartlein barrel. I installed a 20 moa 1pc warne rail 12-42x56 br night force scope with night force ultralight rings. My problem is i am 4 to 5 feet high at the very bottom of the internal scope adjustment. I feel as though i am over looking something simple here. In the fall I picked my rifle up from the gunsmith and installed a 2pc base and a 3x9 burris as temperary situation and had no problems at all. With 3rds i was dialed in and could go from 300 yds to 100 yds and back with out issues. I put the 20 moa base on to do some long distance shooting but should'nt be this high at 300 yds. I have a couple things I am going look at but as of now nothing stands out. Any ideas suggestions or similar expiriences?

 

[TonyR]

I couldn't get my 12X42X56BR with a 20MOA rail to zero at 300 yards either shooting a 284 Shehane but it was only a few MOA high, not a few feet. Is it possible that the rail is not engaging the flat rear level with the round front of the reciever??

 

[DIBBS]

Just a thought, 60 inches high = 5ft =20MOA @ 300 yards.

Not trying to be a smartass... but is there any chance the tapered base is mounted backwards?

 

[moparman]

i just started looking this over a little more in depth and can take a .002" feeler blade around the base at the front and rear and at the back edge only, it seems to try and "catch" or start to insert but nowhere else. i am not able to see any gap but seems to be there only. Would .0015-.002" have this much effect? It is only one the back edge. Thinking about removing the base and double checking for burrs even though none were noticed on installation as i checked before on both surfaces and around threaded and non threaded holes. Both rings appear tight against the rail also.