Floating the bubble "scope shadow"

Discussion in 'Scopes, Optics, LRFs, Spotters, BoreScopes' started by AJC, Oct 5, 2018.

  1. AJC

    AJC

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    I was shown a technical way of verifying point of aim in a scope. Back up from the eye piece until you see the black shadow. Then you have a bubble to float to center so you know your eye is centered. It seems opposite of what is taught on how it should be done but it I initially seems to be working to good effect. Any thoughts?
     
  2. BoydAllen

    BoydAllen

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    I take it that your scope is not adjustable for parallax. If it is, and the adjustments are properly done, if you can see the image, you are good to go.
     
  3. AJC

    AJC

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    Using a NF br 12-42 and a nxs 5.5-22 both 56
     
  4. BoydAllen

    BoydAllen

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    If your scope is properly adjusted, front or side and back, eye position is irrelevant. You should have no parallax at all, and your target should be perfectly sharp.
     
  5. 1shot

    1shot Site $$ Sponsor

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    If I'm reading the OP correctly he is talking about having the eye far enough away from the ocular lens that is creates a shadow. When there is an equal amount of shadow visible, the aiming point and cross hairs are properly centered, hence the "floating bubble".
    I have seen this done where a small hole is drilled in a lens cover to simulate a rear aperture of iron sights. This will force the shooter to have a correct head position and cheek weld every shot.
    @AJC
    Is this what you are talking about?

    Lloyd
     
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  6. AJC

    AJC

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    Yes that is exactly what I mean. I was shown how you can move your head left to right on a full view and the point of aim will move. With the bubble you cant do that.
     
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  7. BoydAllen

    BoydAllen

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    If you can make the cross hairs move on the target by moving your eye around behind the scope, and you are sure that you are not moving the rifle or bench as you do it, your scope is definitely out of adjustment if it has an adjustable objective or side focus. The method that you have described is for scopes that do not have either of those adjustments, which is more typical of less expensive and/or low power scopes designed for game hunting. I have used it for those scopes, when shooting at a target. Another trick is to determine what distance that your fixed focus scope is set for, and place your target at that distance.
     
  8. SFGUY

    SFGUY Gold $$ Contributor

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    The three parts of sight alignment and sight picture include the front, rear, sights, and the eye. The ‘bubble’ he means is the ocular center of the scope and it will only appear perfectly round when the eye is centered. It is a valid test but is more useful to teach what parallax free looks like. Most people think you can set parallax once and you are done. Not so. It has to be checked each day and at each distance. This is one of the problems i see with the wanna-be sniper matches, engaging a bunch of targets in a short period of time. More range time and time looking through the sights helps but only perfect practice makes perfect performance. Also, really important here...if you get 5-6 shooting tips think hard about them and only try them one at a time! Too many variables and you will really get confused. Shoot safely
     
  9. brians356

    brians356 Gold $$ Contributor

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    Last edited: Oct 7, 2018

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