Scope, rings or rifle??

[BowNut]

I mounted a Vortex 6.5-20 Viper on a 223 12BVSS using Burris signature rrings with inserts. Visual boresight was dead on with scope at 25 yards. Looked same at 50 yards. Took gun to range and POI was 10 inches high and 3 right at 25 yards! Tried different ammo and double checked all screws. No effect, back to house. I used the 10 moa inserts to offset difference to help save adjustment on scope. Checked boresight again and still looked zero. Shot rifle and still had about same POI. I adjusted scope to bullseye, backed off to 50 yards and tried again. Ran out of adjustment and still 2.5 inches high. Required another inch of horizontal to zero. At 100 yards horizontal is good, vertical about 5 inches high. Pulled bolt and boresighted, bore on target, scope is 3 feet high and a foot right???
Is the scope bad? Bad rings or bases. Or is it in the rifle? Ive never seen a boresight look that good and POI be so far off. Fairly disgusted at this point. AWESOME grouping, just too far off.
Suggestions?

[Texas Solo]

What type of base are you using? I seriously doubt it's the scope, especially as you say that grouping is awesome. I've seen bore sighting be dead on or waaaaayy off. Are you actually bore sighting, or just looking through the barrel? If the latter....far from accurate.
Did this rifle have a scope on it previously, or is it a new rifle? If new, it is possible, that the the holes are improperly drilled in the receiver, but that's pretty rare.
Use a 1 piece base with 20MOA if you plan on going long distance. I personally never put much faith in the MOA insert type rings as they only make contact in two small places,
where the 1 piece base is graduated 20MOA throughout it's total length. Two piece bases just stink.

[BowNut]

Bases are two piece weaver mounts. looking through the barrel for boresighting has always been very close for me in the past, guess I may have been lucky til now. Rifle is new. I had been thinking about one piece mounts but went with two piece because I'm hand feeding rounds and wanted the extra finger room. Suggestions on one piece 20 MOA?

[yobuck]

How did you tighten the scope rings? Chances are they are too tight causing the erector system to not function properly.
If you did not use an inch pounds torque driver set at 15# this could be your problem. Check that first then shoot it again.
If that fails call Scott Volte, Vortex rep @ 608 836 0922.

[Texas Solo]

Bases are two piece weaver mounts. looking through the barrel for boresighting has always been very close for me in the past, guess I may have been lucky til now. Rifle is new. I had been thinking about one piece mounts but went with two piece because I'm hand feeding rounds and wanted the extra finger room. Suggestions on one piece 20 MOA?

I would DEFINITELY scrap those bases. I'm willing to bet that's 99% of your issue. Get a one piece base, 20 MOA, and torque it properly. I use 20 INCH pounds without anything coming loose.
Don't worry about the "finger" space, you'll be fine. My .223 ammo with 80gr Bergers are crazy long to reach the Wylde chamber, and I hand feed them easily. The benefit of a one piece base far exceeds any perceived pitfalls. I personally have a Weaver base on my .223. It's not as fancy (or expensive) as others, but I can shoot sub MOA at 500yds, so I guess it's OK.
Lose the 20MOA inserts in the rings, torque them properly (16 INCH pounds),put on a good base and see what happens.

[Smokey262]

If it were me I would use the -20 insert on the bottom of the rear ring, the +20 insert in the top of the rear ring, the +10 insert on the bottom of the front ring, and the -10 insert on the top of the front ring. Then I would optically zero the scope and shoot it at 25 yards and see what happens. I would expect the POI to be a little higher than the POA, but not 10".

http://www.burrisoptics.com/pdf/Sig_rings.pdf

This is presuming you have those inserts.

I suggest this because buying a 20MOA base and new rings will be lots more expensive than simply swapping inserts, you indicated that the groups are fine just in the wrong spot, and you don't care if your bore sighting scheme gave you funky results as long as groups are good.

Let us know what you find out.

[short round]

One thing to think about is 1/4" adjustment @ 100 yds, becomes 1/8" @ 50 yds, & is 1/16" @25 yds. Due to trajectory of the bullet a 50 yd sight in will put the bullet high @ 100 yds. The 10 moa inserts, are not for 100 yds.

[BowNut]

Thanks for the input. I'll try to answer all the points covered; rings are torqued to 20 using wrench, I only have the zero and .010 inserts that came with rings, using one piece base is sounding like the answer. I did not buy the zee rings for purpose of increasing MOA, just to help offset any initial alignment problems without using scope turrets and going with the theory that any small misalignment of rings would be corrected by the self centering action of inserts and would prevent damaging tube.
Question on 20 moa base; can it be installed backwards? If I'm shooting high now, wouldnt this make it worse or is the train of thought that the new base will put POI back in center?
The bases were free with rifle(gun shop bonus) so buying a new base is not a problem. I just want this thing right with no worries later. If different rings and base combo is better, still ok with that.

[earl39]

What are you going to use the rifle for and what distances are you going to be shooting as a max? You may not need a canted base. One piece base is less likely to put stress on the scope. Have you checked the alignment of the mount screws with the barrel? More than one has been off due to the action warping a bit when heat treated.

[Texas Solo]

Thanks for the input. I'll try to answer all the points covered; rings are torqued to 20 using wrench, I only have the zero and .010 inserts that came with rings, using one piece base is sounding like the answer. I did not buy the zee rings for purpose of increasing MOA, just to help offset any initial alignment problems without using scope turrets and going with the theory that any small misalignment of rings would be corrected by the self centering action of inserts and would prevent damaging tube.
Question on 20 moa base; can it be installed backwards? If I'm shooting high now, wouldnt this make it worse or is the train of thought that the new base will put POI back in center?
The bases were free with rifle(gun shop bonus) so buying a new base is not a problem. I just want this thing right with no worries later. If different rings and base combo is better, still ok with that.

Get the 1 pc base. No, it cannot be installed backward to my knowledge.
Forget that your shooting high now, you're starting over. The 20 MOA base will give you major adjustability at long range. It simply changes the range of scope adjustment available. Your Vortex Viper has 65 minutes of adjustment in both windage and elevation. That's 32.5 minutes in either direction, up or down. By using a 20 moa base you change that to 12.5 down and 52.5 up.
That will be necessary to shoot 600+ yards. You should have no problem getting 100 yard zero with that range of adjustment, but some 1000 yard shooters, using 30MOA bases, can't get down enough for a 100 yard zero, so they simply zero at 200 yards.
I personally don't care for the adjustable rings. If things won't line up good without them, you have other issues. Given the quality of your rifle and scope, I doubt you have other issues.
Now get a quality 1 pc base, quality rings, and go shoot some groups!

[big honkin jeep]

Go ahead and exercise your scope by turning the adjustments both horizontal and vertical throughout their full range of adjustment several times. (I always do this with a new optic usually until my fingers are tired). While you're doing this count the clicks so you can set it back to its optical center and then do so.

Take the rings and bases apart and reinstall. Sometimes base screws are too long. To be sure the base screws aren't bottoming out against the bolt I would go ahead and remove the bolt while reinstalling them. If the bolt wont go in after you've installed them you know the screws are too long. If the base isn't locked down tight but the screws are tight they are too long.

Check to be sure the bottom rings are sitting properly in the base and are all the way forward in the base slots and tighten them.(so they cant shift under recoil) Put the scope back in the rings adjust it where you want it and carefully tighten being sure to maintain proper position.

Pull the bolt and bore sight. I usually do this by looking out a window and picking a distant object with my rifle in a cleaning cradle. The objects I choose are lot further than 25 yards usually the most distant suitable point I can find. The top of a neighbors plumbing vent stack(2"pipe) sticking up from his roof works for me.
hopefully you'll still be within 15 clicks or so of your optical center.

Go to the range and and squeeze one off. You should be on the paper at 50 yards.
Then preferably put your rifle in a cleaning cradle or steady rest. Put the crosshairs on the bullseye and then without moving the rifle turn the adjustments until the crosshairs are on the bullet hole. Back up to one hundred yards and repeat.
Your rifle should be zeroed and ready to rock. If you find that your bases and rings are incompatible a good set of standard Leupold or Burris rings and bases (components that match) would be a great place to start.
Good luck

[BowNut]

Lots of good information guys, thanks. I think my plan of action is a one piece 20MOA base, new rings and start fresh. Spare parts never hurt, plenty of guns at home. I know the screws were ok with current bases, but I will verify new ones. I will work the turrets full directions and recenter scope. probably bed the base as extra measure when I bed the action to eliminate other potential problems. I made an insert to convert to single shot vs the blind magazine, checked it about ten times to make sure it has proper clearance and doesnt bind on action. weather and job has kept me from getting things done and shooting much since I bought the gun. Going to be on job for next two weeks so redoing scope is going to wait too, plenty of time to find the parts.
This rifle is going to be target and occasional varmints. I plan to play with longer range shooting, to 600 i hope, so the base will be a good start.
I appreciate the help guys. I'll post results when I get new base fitted.

[BowNut]

I'm back to square one. Tried new base, Warne 0 MOA single piece, Warne rings. Centered scope mechanically, verified using mirror. Removed bolt, boresighted visually and also used a laser cartridge to check scope alignment; laser showed about two inches low and left at 50 yards. Fired four rounds, all four within 1 inch group......8.5 inches high and 4 right at 20 yards. I swapped scopes, went through same boresight steps....same results, maybe an inch higher.
I tried to adjust scope and ran out of adjustment and was still inch high.
Bedded rear pillar because it felt spongy when tightening action. No effect on POI.
I'm back t thinking its the rifle, but not sure how boresight can be so far off from POI.

[earl39]

One more thing to try when using a rail is turn your rings around so the bolt head is on the other side. You can also switch them front to rear. Sometimes it makes a difference.

[Oscarflytyer]

My bore sight was off by about 8" at 25 yds. Not unusual in my experience. Why I don't usually waste my time bore sighting. This one was only because the store did it for me.

[BowNut]

In order to get scope to zero, I'm going to have to shim front of rail. Is this common? I hate to think for the price of this rifle that it would be that far off. I'm waiting for Savage to give me their ideas.