Schmidt & Bender Parallax vs. Non-Parallax

Discussion in 'Long Range Scopes and Other Optics' started by OnTarget, Mar 17, 2006.

  1. OnTarget

    OnTarget Member

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    I recently saw a PMII 3-12x50 for sale that had no parallax adjustment and it was stated it was calibrated for shots out to 300yds. So does this mean beyond 300yds that the scope wouldn't perform well? At what distances would the scope absolutely become impaired for use without the parallax feature? I would think that this could be generalized to other scopes without parallax, correct me if I'm wrong. Thanks.
     

  2. Bart B

    Bart B Well-Known Member

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    First, there is no such thing as parallax adjustment. That’s the wrong term to explain or name what you’re talking about. I don’t care what rifle scope makers say or put in print. “Calibrated” is also the wrong term.

    Focus adjustment is the correct term. Your scope does not have an adjustment for its front lens to focus the target image on the reticule. If the target image isn’t focused on the reticule but is focused in front of or behind it and your aiming eye is centered in the scope’s optical axis, nothing bad will happen unless the range is very short such as 75 yards or less. Then the target image may be a bit out of focus but still seeable. If you move your aiming eye a bit off center the reticule will appear to move a little bit but at short range it doesn’t matter; this is parallax but if you move your eye back to center the parallax goes away. It’s the same thing as looking at your car’s speedometer needle against the scale. As the driver, you see the needle aligned exactly on 60 mph but the person in the passenger seat sees the 55 mph mark aligned behind the needle; he has the parallax problem but you don’t. If the passenger sits in the driver’s seat he doesn’t have a parallax problem reading the speedometer but you would sitting in the passenger seat. The error seen from the passenger seat depends on the distance between the needle and the markings on the speedometer’s face. Look up ‘parallax’ in your favorite dictionary.

    Your scope is probably focused at some point between 100 and 150 yards. Target images will appear clear from 60 or so yards all the way past 1000 yards. Put your rifle on a rest then look through the scope at targets located at several ranges. Move your aiming eye around and see if the reticule appears to move on the target. If it does then parallax exists. Note how much the reticule appears to move and that’s the amount of aiming error cause by parallax you have. It typically isn’t very much. There’s nothing wrong with your scope. It just isn’t focus properly at very short ranges.
     

  3. OnTarget

    OnTarget Member

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    Bart, I really appreciate your reply and your analogy with the speedometer it clarifies much. What I would like clarification on, is a 'Parallax equipped scope' for someone who doesn't trust their ability to use their aiming eye to center in the scope’s optical axis? If you look at S&B line you will see in the 4-16x50 'parallax adjustment' isn't an option, but only come standard with the scope: http://www.schmidtbender.com/scopes_variable.shtml Of course having the "parallax adjustment" built into the scope increases its cost to the point in the PMII line that it adds approximately $600 to the cost. I'm just trying to understand if you know your equipment well enough can you avoid buying a scope with parallax and its associated cost or is their a point when shooting at distances (beyond 500, 600, 700 yds??) that it becomes a necessity? I didn't buy the S&B 3-12x50 without parallax, a dealer has it and has been unable to sell it and is willing to let it go for $1400 because in their words, "we've had it for a year and we haven't been able to sell it because it doesn't have parallax." So either their is some application where the parallax adjustment is needed or people buying S&B scopes with parallax have more money than sense at an additional $600 for the option. If I can avoid the cost of the parallax option by only needing to consistently position my aiming eye to the center of the scope's optical axis then I save a lot of money. Any additional clarification is appreciated.
     
  4. Bart B

    Bart B Well-Known Member

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    I went to the S&B web site and looked at that scope. It’s adjustment is marked in range so the front lens system can focus the target image on the reticule. It’s marked and works just like a camera lens; focuses for range. And the additional $600 for a scope with range focus is a bit out of line in my opinion. One can buy a Weaver V16 4x-16x variable with focusing objective and 1/4 MOA click adjustments for much less than 600 bucks and it’s probably one of the best rifle scope buys on this planet; very good optics and mechanics. Having looked through S&B rifle scopes their optics are no better than scopes less than half the price. Your comment “...or people buying S&B scopes with parallax have more money than sense at an additional $600 for the option.” is a good observation. I wouldn’t pay that much extra for it; there’s excellent rifle scopes with adjustable objectives for a lot less money.

    If you position your aiming eye as far back as possible to see the entire field of view, it will be at or very, very close to the scope’s optical axis. With that scope focused at 100 or so meters, there may be enough parallax with your eye way off to the side to have a 1 MOA or more error at very long ranges. Which is why it’s best to have a range-focusing (adjustable objective) scope for targets beyond 300 yards if one has problems keeping their aiming eye on the scope’s optical axis. Plus, focusing any high-magnification scope right on a target past 600 yards will make it clearer and easier to distinguish its features.
     
  5. Pete Lincoln

    Pete Lincoln Well-Known Member

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    Guys, the S&B scopes are worth the extra cost, they are that much better. Ask the US Marine Corps.

    I used a 3-12x50 PMII with illuminated ret ( no paralax adjustment) for years for long range shooting, so long as you remember your marksmanship principles and get your head and eye in the right position you will be ok.
    Paralax adjustment is however a very desirable extra.

    The 3-12x50 non paralax can be had over here new for about $1600.
    I'd call $ 1200 - 1300 a bargain.
    Pete
     
  6. sfor

    sfor New Member

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    As far as the quality and results of Schmidt & Bender, they are the choice optics for most Candian Forces Sniper Detachments in Afghanistan, the PMII line is used medium range on
    the Timberwolf in 338 lapua and 7.62 with the AR-10T, as well as for long range use on the
    MacMillan Tac 50. Everyone loves'em, ...except the Taliban
     
  7. Jamie6.5

    Jamie6.5 Well-Known Member

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    I would never argue the quality of an SB scope. But the problem of parallax, especially in the field, and at long range is a definite problem.
    From the bench, prone or other target shooting, with a target rifle/stock combination, and repeatable rest, it can/should be less of a factor.
    Consistent cheek weld and eye alignment is less of a problem under those conditions.

    In the field, in the "heat of the moment" when a trophy of a lifetime is your target, perfect cheek weld and eye alignment may easily be forgotten.

    For hunting, get the one with parallax adjustment.

    My $.02, YMMV.
     
  8. Jon A

    Jon A Well-Known Member

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    The 12X scope with parallax set for 300 will work well at long range. There is very little adjustment between 300 and infinity on S&B scopes; the amount of parallax error will be small.

    The problem will be load development at 100yds. That will be a PITA as shooting small groups will be difficult. Do load development at 300 yds and be happy. I'd use the scope without hesitation.