I’m baffled....

Discussion in 'General Airgun Chat' started by Halesowen Kid, Sep 6, 2019.

  1. Halesowen Kid

    Halesowen Kid Member

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    Hi Guys,

    Your help please...

    I have three .177 rifles, being two pcp’s, a Daystate Regal R, an AA S510 R and a HW98 springer.

    The pcp’s powers are 11.5ft/lb and each rifle is fitted with a Hawke Airmax scope set at mag of 10 and on on medium mounts and firing Daystate, JSB or AA Field all 8.44 grain.

    The HW98 power is 10.6ft/lb and is fitted with an MTC Viper 10x42 scope on medium mounts and firing AA Field 8.44 grain.

    My question is at 50yds my hold over is 1 mil dot for each pcp rifle, yet I need 1.5 mil dot hold over on the HW98 to hit the same POI on the target.

    Is it that I need to up the power on the HW or would it be the differences in the two makes of scopes that is giving me this variation?

    I’m looking to achieve the same hold over for whatever rifle I shoot.

    I look forward to your replies and I thank you in advance.

    Mike
     
  2. AdyT

    AdyT Member

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    Some of it will be power, even though you have medium mounts on both, is the distance from centre of your scope to centre of the barrel the same.
    Ady
     
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  3. garym

    garym Active Member

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    The lower power on the HW 98 is the issue.
     
  4. Halesowen Kid

    Halesowen Kid Member

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    7mm difference Ady
     
  5. Halesowen Kid

    Halesowen Kid Member

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    Cheers Gary’s....
     
  6. Adam

    Adam Well-Known Member

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    It’s mostly the power difference but any difference in scope height will alter things too. Chairgun is great for visualising these things.
     
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  7. rich

    rich Active Member

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    One mildot at 50 yards on 10x mag sounds like the PCP rifles are zeroed so that the pellet rises above the optical sight line. Maybe the springer isn't.
     
  8. Conor

    Conor Never been banned from sales Staff Member

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    It’s pretty simple really.
    PCP is almost 1ft/lb more powerful, it’s running around 785fps, the springer is running closer to 760fps.
    Scopes also are different and possibly a slight difference is reticle calibration.
     
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  9. SteveC200

    SteveC200 Well-Known Member

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    Are they zeroed at the same distance?
     
  10. Halesowen Kid

    Halesowen Kid Member

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    Yes, 30yds Steve
     
  11. BDL

    BDL Dangerous

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    The difference will be in the velocity you have about a 30fps drop so this will be a major factor.

    Bri
     
  12. fireblade

    fireblade Team AirArms

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    Or you could just zero the springer around 40 yards ( a bit of trial and error until you get it right) to get the pellet landing on the first mil dot at 50, that's if you don't want to start messing with power or scope height.
     

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