Boresighting

Discussion in 'Long Range Hunting & Shooting' started by eferry, Aug 15, 2010.

  1. eferry

    eferry Active Member

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    I most recently purchased a 300 ultra mag and wanted to get my scope bore-sighted in...Any recommendations on purchasing a laser boresighter?

    Is it better to laser-sight this in @ the shooting range @ 200 yards?
    Or should I sight this in using the basic instructions @ 25 yards or so on the paper target?

    Your thoughts and opinions are greatly appreciated.
    Thank you.
     
  2. joseph

    joseph Well-Known Member

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    I think you should I sight this in using the basic instructions @ 25 yards or so on the paper target then move to 100 yds then move out even farther.

    joseph
     

  3. SBruce

    SBruce Well-Known Member

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    Plus 1 for starting at 25 yds.

    I've never used a laser boresighter, but I've used a couple other types. My experience has been that they will get you "on paper" at 100 yds......not actually sighted in exactly..........that's always required real shooting.

    If you use a target w/ inch grids on it, you can easily figure the amount of adjustment needed after your first shot hits the paper. Usually, only a few shots are required for a zero then.
     
  4. jeffro

    jeffro Well-Known Member

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    Pull the bolt. Look through the bore at a sheet of paper @ 100 yrds. Set up the scope. After I do this I can hit the 8.5x11 paper on the first shot. Move your eye as far back as you can. This will help you to get closer to your dot on the paper.
     
  5. Dr. Vette

    Dr. Vette Well-Known Member

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    I use this boresighter:

    Site-Lite SL-100 Mag Laser Boresighter with SRL-100 Rifle Scope Reticle Leveler - MidwayUSA

    I also use this:
    EXD ENGINEERING : EXD ENGINEERING VERTICAL RETICLE INSTRUMENT - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools

    before hand so that I know my scope is over my bore, also using a bullet level on top of the turret to be sure the scope is level. Once I know that the scope is exactly over the bore and the scope (and therefore crosshairs) is level, I get to work. Some people also use a "hanging string" to see if their crosshairs are correct; either way works.

    You can use a 25 yard mark, but I don't.
    The garage door across the street is 100 yards away. I use this program: Handloads.Com Ballistic Calculator to check how much my bullet is going to drop by 100 yards. As an example if I want the bullet to hit 2 inches high at 100 yards, and it's going to drop 2 inches by 100 yards, then I want the laser dot to show about 4 inches above the crosshairs when I project it on a 100 yard object.

    Doing this I can get very, very close. Your horizontal alignment will probably be exactly correct but your vertical may vary a bit. This system has worked for me for several rifles in the past year. "YMMV"
     
  6. Troutslayer2

    Troutslayer2 Well-Known Member

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    I also pull the bolt and look at something downrange- as far away as possible, like a distant telephone pole. I center the bore on that while the gun is resting in the vise. Then I move my crosshairs until they are on that same object. Always gets me on paper at 100.
     
  7. fj40mojo

    fj40mojo Well-Known Member

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    +1, no need to buy a laser bore sighter. This works just fine. Gets you on the paper first shot unless you are using a MOA base in which case the line of sight through the bore has little to do with the view through the scope, but it can still be done without purchasing another piece of gear that you won't use enough to justify buying it.
     
  8. jeffro

    jeffro Well-Known Member

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    Even with a MOA base you still have to move the cross hairs down. It works just the same as with out a MOA base. I do this to all rifles, MOA base or not.
     
  9. silvertip-co

    silvertip-co Well-Known Member

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    save yer $$$ pull the bolt and look downthe barrel. i boresight all my stuff and others stuff on my neighbors F350 wheel center. never fails to get me within 4" of center on target on first shot.
     
  10. justgoto

    justgoto Well-Known Member

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    I use an "L" shaped square. I'll open my box magazine, put the square on the open box mag then spin my scope until the windage cap is parallel to the square.

    I am sure there are all sorts of surfaces you could use a square against, the box mag on my rifle is handy.
     
    Last edited: Aug 18, 2010
  11. bigbuck

    bigbuck Well-Known Member

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    +1 I also pull the bolt. The trick is make sure you do not touch the rifle except for turning your dials I set my rifle up on sand bags and let the bags hold the gun perfectly still . then i simply watch the cross hairs walk over to the little orange dot at say 50 yards I fire one shot at 50 but probly don't need to then i'm on the paper @ 100 every time.

    BigBuck