A little help please

Discussion in 'Long Range Scopes and Other Optics' started by ENCORE, May 12, 2014.

  1. ENCORE

    ENCORE Well-Known Member

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    Yesterday while attempting to shoot 500yd targets, I found that I ran out of scope adjustment. The backstop is a 4'x8' sheet of OSB board and I stapled two targets on top of a couple 1,000yd targets someone didn't pull down after shooting. I stapled them down about 10" from the top of the board.

    I'm shooting an Ultimate Firearms muzzleloader, not a centerfire. The scope is a Leupold VX6 3-18 with a custom turret matched to my loads. With a 200yd zero setting of the turret, its dead on at both 300yds and 400yds. The turret has a maximum of 450yds marked.

    Long story shorter, I maxed out the turret adjustment and backed off one click, then sent six rounds. I didn't hear the bullets strike the backstop. Because the range is still wet, you have to walk to the targets, which I did and found that I didn't hit the backstop. After walking back and settling down, I sent six more rounds holding at the top of the backstop. Each round hit the backstop but, very close to the bottom.

    Ok..... I understand to shoot that range, I'll need a different base. To those with lots of long range experience, will a 10 moa base give me enough elevation or, should I go to a 20 moa base? I don't want to go so far with a base, that it prevents me from a 100yd zero.

    I'll very much appreciate some long range shooters suggestions.
     
  2. MMERSS

    MMERSS Well-Known Member

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    Your scope should have approximately 75 MOA total elevation adjustment (check to verify). A 20 MOA base will provide approximately 17 MOA for downward adjustments and 57 MOA for upward elevation adjustments. Without an MOA base you have approximately 37 MOA each direction.

    If you are at the end of your elevation now while shooting the top of a 4’ piece of plywood while hitting the bottom you need approximately 50” of adjustment. A 10 MOA base may not quite get you there, or it may however your scope will probably be maxed out in elevation again.

    Go with a 20 MOA base and leave yourself plenty of room and a little more room for adjustment and distance if needed.
     
  3. ENCORE

    ENCORE Well-Known Member

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    Thank you. Will it still allow me to have a 100yd zero?
     
  4. 42769vette

    42769vette Well-Known Member

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    How much drop does your muzzleloader have from 100-500?

    Unless your round has 50 MOA of drop from 100-500 you should easily be able to get a 100yd zero with the 20 moa base ASSUMING your scope has the advertised travel wich is not always a save assumption.
     
  5. ENCORE

    ENCORE Well-Known Member

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    Using my software, it states with a zero at 100yds, it drops 117.75" at 500yds.

    I set the zero for the rifle to 200yds, which makes it 4" high at 100yds. Shooting Parker 300gr BE's @ 2350fpsm


    Scope is a Leupold VX6, 3-18x50 w/custom turret, illuminated dot.
     
  6. MMERSS

    MMERSS Well-Known Member

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    In theory yes. Another simple check is place your elevation on your 100 yard zero then see how many MOA you can "dial down" until your turrets start to bottom. If you can dial down around 26 or more MOA you can use a 20 MOA base and still have some comfort room with a 100 yard zero.
     
  7. 42769vette

    42769vette Well-Known Member

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    Your more than fine.
     
  8. ENCORE

    ENCORE Well-Known Member

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    Thank you!