Tempreture changes in power

Discussion in 'General Airgun Chat' started by RAIDER, Jun 24, 2014.

  1. RAIDER

    RAIDER Member

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    If you guys as I was were convinced that the hotter your rig got out in the sun, think again.
    I read an article in june edition of BASC magazine regarding "boyles law".
    Basically the guy had all the chronos from the Birmingham proof house plus their scales and done a test on various rifles from steyrs to daystates.
    I was totally confused as none of the rifles tested from 10c - 39c, all lost power. YES LOST POWER.
    If you get chance have a look im sure its on line some where.

    RAIDER
     
  2. RobF

    RobF Administrator Staff Member

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    My Walther is gaining 10-15fps at the moment...

    Every year i've seen the same thing in comps... in winter low misses can be found on the plates, in summer, high. Doubt it's to do with rangefinding as i'm sure some scopes are like mine which ranges short when it gets warmer.
     
  3. Tench

    Tench WHFTA World Champion 2016.

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    Tell that to all the people who dropped out the bottom of the long kills with their Steyr's during the sub zero Daystate Midland round the other winter.
     
  4. nemesis

    nemesis 55yrd standing expert, or was it 8 or 9?

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    My Steyr is the same during winter and summer. I set my velocity to the conditions on the day.l don't add or remove clicks on the scope.
     
  5. RAIDER

    RAIDER Member

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    Temp

    Hey guys im the messenger here. Im just saying that in the BASC magazine is what "they are saying" not me.
    Get a copy and read, if I can get hold of it again i'll paste it on here. Some one must have the copy.
    RAIDER
     
  6. Gary Martin

    Gary Martin sultans of spring

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    as everyone else

    i have the same experience as every one else. warm, velocity increase, and vice versa.
     
  7. Tench

    Tench WHFTA World Champion 2016.

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    I wasn't shooting the messenger, just saying that those findings go against what some people have experienced. It could be dependant on viscosity of lubricants, or indeed whether the gun is run dry or not.
    I would like to see the same tests performed down to a few degrees below zero, I would be very surprised if that didn't show a drop in velocity.

    And since when has Susan Boyle been into air rifles! :)
     
    Last edited: Jun 24, 2014
  8. RobF

    RobF Administrator Staff Member

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    So it's the same but you set it each day???
     
  9. nemesis

    nemesis 55yrd standing expert, or was it 8 or 9?

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    Only marginal changes approx 20 fps,from one extreme to another.
    I haven't noticed massive variation from say 2deg to 28deg.From getting the gun out from one week to the next the variation is at the very most 20 fps, most of the time it's about 10 fps from the last time I use it.
    I don't get say 50 fps variation from extreme cold to hot.

    I
     
  10. Delphinus

    Delphinus New Member

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    I agree the power changes with temperature but there's also another factor for the misses, the air density, when is cold is higher and pellet has more resistance in the flight and the opposite with hot weather. :lev
     
  11. villiers

    villiers Self appointed antipimp

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    My Walther +/- 15fps summer to winter. metal and lube / o ring material change it would be a fantastic stable gun not to change in a 0 deg to 30 deg window.
     
  12. hmangphilly

    hmangphilly Not quite a full phil

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    what does that bit mean don ?

    your tip about keeping the hammer clean was spot on
     

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