scope unlevel (cant)

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Cassman, Oct 20, 2019.


Help Support Long Range Hunting by donating:


  1. Bravo 4

    Bravo 4 Well-Known Member

    Messages:
    3,404
    Joined:
    Jul 20, 2007
    Well that is just embarrassing...on my behalf!:oops: You are correct. I’ll just go sit in the corner. Nothing to see here folks, carry on.
     
  2. gohring3006

    gohring3006 Well-Known Member LRH Team Member

    Messages:
    3,810
    Joined:
    Mar 17, 2014
    It’s probably cant. Do a tall target test like recommended above.
    Levels are just a baseline. Setting the rifle up for consistent hold, then using a plum bob to plum the reticle is best after initial set up.

    ps, don’t worry about rifle cant, just concentrate on a hold that you can repeat every time you get behind the rifle. After plumming the reticle, set your anti cant level on the scope tube.
    All confirmed with a tall target test of course.
     
    Mram10us and Bill Cauley Jr like this.
  3. jimbires

    jimbires Well-Known Member

    Messages:
    1,382
    Joined:
    Mar 16, 2008
    the tall target test is explained in post #3 , the first link I posted .
     
  4. Cassman

    Cassman Member

    Messages:
    5
    Joined:
    Nov 23, 2016
    thank you very much,,i have read both links,,great info I needed to read...
     
    jimbires likes this.
  5. ShtrRdy

    ShtrRdy Well-Known Member

    Messages:
    2,257
    Joined:
    Jan 14, 2012
    Long Range Shooters of Utah did a demonstration of the change of bullet impact with rifle cant. He said he is shooting at 925 yds.

     
    Cassman likes this.
  6. Mram10us

    Mram10us Well-Known Member LRH Team Member

    Messages:
    583
    Joined:
    Oct 19, 2019
    Refreshing to hear people doing tall target tests!
     
    DENWA likes this.
  7. jimbires

    jimbires Well-Known Member

    Messages:
    1,382
    Joined:
    Mar 16, 2008
    when I dial a scope for elevation , I do a tall target test .

    when I'm using a ballistic reticle , I true the reticle to a plumb line , weighted rope , etc . examples would be a Leupold Boone and Crockett , Ziess rapid 600 or 800 , there are many more
     
    Mram10us likes this.
  8. Mram10us

    Mram10us Well-Known Member LRH Team Member

    Messages:
    583
    Joined:
    Oct 19, 2019
    Jim, same thing. Another note, I prefer my tall target test to be slightly left so I don’t have to mess with spin drift. Takes another thing out of the equation since mine are for hunting and not br score
     
  9. TheLongRanger83702

    TheLongRanger83702 Well-Known Member

    Messages:
    97
    Joined:
    Feb 20, 2015
    I owned an expensive Luepold scope. I wasted a lot of ammunition trying to figure out a similar problem. I ultimately discovered that the reticle was NOT squared with the scope body. When making either elevation or windage adjustments they were both way off. I replaced the scope.
     
    DENWA likes this.
  10. Greyfox

    Greyfox Well-Known Member

    Messages:
    5,196
    Joined:
    Jan 21, 2008
    The last several rifles that I have set up had the scope reticle/scope level adjusted by projecting the reticle on my basement wall with a plum-line, and aligning the reticle and level to the plumb-line. ALL the 100 yard tall tests performed on each in the field were “nuts on” with no further adjustment required.
     
    DUSTY NOGGIN, Bravo 4 and sedancowboy like this.
  11. sedancowboy

    sedancowboy Well-Known Member

    Messages:
    319
    Joined:
    Nov 28, 2014
    You might check the alignment of the scope base mounting holes vs the barrel. Often these are not in perfect alignment and you have the condition you describe. In this case the Burris Signature rings with the inserts are your friend. I have used a 30" Al rod 1" in dia to test the alignment of the scope bases before. I have also made sure the scope reticle was centered and them use a bore sighter to see it they align.
     
    DUSTY NOGGIN likes this.
  12. Pete Callamaras

    Pete Callamaras Well-Known Member

    Messages:
    208
    Joined:
    Feb 15, 2019
    Did you lap the mounts? IF the mounts are not lined up correctly (, and the scope completely seated (in lapped mount), then you can get some weird results. Don't ask me how I know that...………
     
  13. Kerryt38

    Kerryt38 Active Member

    Messages:
    25
    Joined:
    Apr 11, 2014
    If you are canting your rifle it would also either be shooting high or low by a similar amount. If you aren’t experiencing that too then there is another issue.
     
  14. snox801

    snox801 Well-Known Member

    Messages:
    2,635
    Joined:
    Sep 19, 2012
    Like other said that would be a ton of cant.
    I have found out that even if I think it’s perfect at 100 it’s off a bit at 200. So I e since started using my side to side zero at 200 with a calm day. Then when I go back to 100 it’s always on. 300 yards seems like you may be off a smudge left to right with the wind not helping.
    Try a segway leveler. It’s only about $20 and works great. I have no issues with that setup at 300 yards.
     
    Cassman likes this.