What are these Infa red screens supposed to do?

Discussion in 'Equipment Discussions' started by Iron Worker, Mar 22, 2010.

  1. Iron Worker

    Iron Worker Well-Known Member

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    Today at the range it was a bright sunny spring day.My velocity reading were a 100 FPS slower then last time on a semi cloudy day. Same loads in the cartridges. What's up with that ? Is this infa red screen tech suppose to help ?
     
  2. phorwath

    phorwath Well-Known Member

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    What brand / model chrono are you using?

    Here's a link that describes the benefits of the infrared screens and provides some additional educational information on the use of chronographs in general:
    CED M2 Chronograph

    This paragraph is taken directly from the above link:

    5.The CED Infrared screens are designed for use when mother nature is not cooperating or for times and locations where insufficient light exists. If they are used under bright sunlight condition, it is possible that the sunlight may over-power them or create an in-balanced condition. It is critically important on ALL chronographs to maintain a BALANCED light condition on both sensors. Therefore, in such conditions re-position the chronograph to an area of shade away from the sunlight, or remove the infrared screens and use natural sunlight in a balanced position, or cover the infrared screens with a large cardboard to prevent natural sunlight from reaching the sensors.
     

  3. Iron Worker

    Iron Worker Well-Known Member

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    I'm using that exact brand and model CED M2. Today was a very bright day. So I guess that means Infa red screens might not of helped me ? What other tricks can I do on bright days ? Do I need the white hoods or what ever they're called ? My ammo's POA was where is was supposed to be but a 100+ lower then on a cloudy day? Its not fare !
     
  4. phorwath

    phorwath Well-Known Member

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    On full sunlight, cloudless days it is recommended that the sensors have a top hood/cover over them so the skyscreens are looking up at these covers rather than the blue sky.

    I'm surprised the covers aren't supplied as standard equipment with the CED M2. If they are, you should use them on the sunny cloudless days.

    The covers with my Oehler are an orange-colored plastic. The covers for my PACT are white plastic. When it's cloudy out, I don't use them. I do use them on the bluebird days.
     
  5. Iron Worker

    Iron Worker Well-Known Member

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    Oh they came with it and I used them today. An example I'm shooting a 6x284 with a hot charge of Re#17 behind a 70 gr Nosler BT which in the past ( Last time at range) on cloudy day I was getting nearly 4,000 fps. Today that same load 3775 Average. I don't get it ? Thanks for your response ........
     
  6. Iron Worker

    Iron Worker Well-Known Member

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    Thanks Phorwath for pointing me to the directions. I read that if the screens are even 1/16th of an inch off . False readings will result. So my screens weren't firmly locked in. Next time I'll double check that.
     
  7. phorwath

    phorwath Well-Known Member

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    Good deal. Hope you start getting more consistent readings.