Vortex Viper 6.5-20x50 & 300 WM problem

Discussion in 'Long Range Scopes and Other Optics' started by bullelk14, Mar 11, 2012.

  1. bullelk14

    bullelk14 Member

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    I thought I had everything all figured out, then went out to sight in and now have a problem. I have a Win Laredo 300 WM and put a Viper 6.5-20x50 on it with a 20 MOA base ( mounted with thick end to the rear ) and Warne Maxima 30mm rings. When I sighted it in at 100 yds, I only have 6.75 MOA left to go up. Something has got to be wrong somewhere. I figured with the 20 MOA base, the Viper has 65 MOA of adjustment, I would have plenty of adjustment for the approx 25 MOA I thought I would need for 1000 yards. I assumed the 100 yard zero would be almost at the very low ( down ) part of the adjustment, but it took quite a bit of up to get it on at 100, leaving me not much left. I am very new to this, am I missing something? What is it gonna take to get this set up ready for long distance? Thanks in advance for any suggestions/telling me where I screwed up.
     
  2. trazman

    trazman Well-Known Member

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    Have you tried if your target turns 65 moa without sighting? Maybe it is a manufacturing problem...
     

  3. Gene R.

    Gene R. Well-Known Member

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    Shouldn't the thicker end be at front of reciever? This would raise the the scope plane from the bore. Hence you would lower the elevation turret to match the plane of the bore for sight in. This should take you into the negative of elevation MOA giving you them clicks now for plus MOA? I don't have +moa base but I think this how it works. Maybe someone else with more knowledge about canted bases will see post and chime in.

    Gene R.
     
  4. highridge1

    highridge1 Well-Known Member

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    The thicker part of the base is at the rear of the action. This causes your bore to point higher giving you more adjustment at long range.
     
  5. Broz

    Broz Well-Known Member

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    Turn your elevation turret from one end of the travel to the other counting the total moa of travel. To make surethe scope does travekl through it's entire range.

    Also with a 20 moa base the scope should be mounted with a slight downward slant towards the muzzle of the rifle and this should be visable.

    It could be that this is an improper base for your recever, maybe mispackaged or something. Or I have seen EGW rails be off by as much as 30 moa. What brand rail is it?

    It sounds to me that you have done everything correctly. I have that same scope on a rifle (AR 15 flat top) and it works great and I dal it to past 700 with no canted rail. So we need to find what is off here with the mounting.

    Jeff
     
  6. bruce_ventura

    bruce_ventura Well-Known Member

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    Yup, sounds like a problem with the barrel/receiver/mount. A misalignment problem of that magnitude should be easy to diagnose. Check the adjustment range on the scope, and confirm that the scope is ok.

    Then I recommend you remove the rings so that you can inspect the mount. Place a 24" straight edge (steel ruler) along the top of the rail. Inspect the top surface to make sure the rail isn't bent. Inspect the alignment of the mount with respect to the receiver and the barrel. Then remove the mount and do the same for the receiver and barrel alone.
     
  7. bullelk14

    bullelk14 Member

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    Thanks for your replies.
    I checked the full travel of the adjustment on the scope and from bottom to top it does 5 full revolutions plus 3.5 MOA, so with 12 MOA per turn, I believe that shows 63.5 MOA of travel. The 20 MOA base is a Weaver, here is a photo of the set up. Just looking at it, there appears to be no bend or malformation. I will pull it off and check with a straight edge. Anyone see anything off just by eyeballing it?
     

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  8. Muttt

    Muttt Well-Known Member

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    Well, I have a Viper 6.5-20 x 50 on my Remington 700 SPS tactical. I am using an EGW 20 MOA base. I originally mounted it using Warne Tactical high rings. When I zeroed it at 100 yards, I was at the very bottom of the travel and 1 inch high at 100 yards. That gave me 68 MOA of travel UP. Although I was happy that I had so much travel available, I didn't want to run the scope on the bottom mechanical stop. And, I wanted to be dead on with my 100 yard zero so my dope would read correctly. So, I replaced the high rings with a set fo Warne Tactical low rings. This shifted my point of impact down 9 inches. This moved me up approx 9 MOA which reduced my amount of UP travel to 59 MOA. I don't see my set up being any different than yours. They are almost identical. There is no way you should only have 6 MOA of travel left. Are you sure you aren't cranking the dail in the wrong direction? With 59 MOA of up travel, I can take it all the way out to 1000 without any hold over at all.


    Give the folks at Vortex a call or email. They are superb peole and will bend over backwards to make things right.
     
  9. loosesniper2000

    loosesniper2000 Well-Known Member

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    By looking at the picture it seems like everything is in place. If I were you I'd borrow another scope (good luck doing that) or try one off your other guns to see if you have the same problem. If you do, then the problem lies within the machined work on the gun/base...etc
    I'm guessing you got a bad scope but that's only a guess.
    Let us know
     
  10. bruce_ventura

    bruce_ventura Well-Known Member

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    I guess the other explanation is that the OP confused up vs down on the turret. That is, at a 100 yd zero the turret was 7 moa from the upper end of adjustment, not the lower end. Might be a good idea to look through the scope again and confirm that the reticle moves 56 moa up, rather than down, from the 100 yd zero. If the reticle moves down (causing objects in the field of view to appear to move up), then there is no problem.
     
  11. bullelk14

    bullelk14 Member

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    Bruce, now you have me second guessing myself. I started with the scope close to bottomed out when I went to zero at 100. I was hitting in the dirt 5 yards in front of the target. I kept twisting it in the direction of the up arrow on the elevation turret until I zeroed at 100. Now, zeroed at 100, I can only twist the elevation turret in the direction of the up arrow 6+ MOA before topping out all the way up.

    We have a new shop near where I live called Idaho Armory, guy who owns it is a pretty distinguished 1000 yard shooter. Think I will run it in and have him take a look at it.
     
  12. trazman

    trazman Well-Known Member

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    If it is so, then the only thing possible is, that the receiver and the mount produces 60 moa of inclination, which means that there is something wrong with the receiver probably, becose if it would be the mount you should se that it is inclined 60 moa, but I don't know if it even exists with such inclination...
     
  13. Coyboy

    Coyboy Well-Known Member

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    swap the rings end for end and see if that makes a diference.
     
  14. bruce_ventura

    bruce_ventura Well-Known Member

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    Bullelk, your description confirms there is an issue with the rifle. A three degree+ alignment error is huge. Seems very unlikely the issue is the scope. Your photo doesn't indicate anything unusual to me. Most likely the solution lies with the 20 moa base. I'm guessing you will have to either replace it or bed it. Having another pair of eyes look at the problem is always a good idea.

    What is the history of this rifle? Is it new, or was there a different scope on it previously?