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Old 26th April 2011, 02:10 PM
neilL neilL is offline
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Join Date: Mar 2010
Member of: NOFTC CRPC
Location: Oxford
Posts: 576

Originally Posted by RobF View Post
Grief, it's hard to type this thread starter....

What would be great is to be able to get two CED M2 IR's together one day, tie them so they are reading the same and do some BC work as well, cos I have a new theory as to why sizing might reduce vertical spread on pellets.
I saw a few go left and low even though I was in a comfortable position and well within ranging comfort. It was almost as if the side gust slapped the pellet (gap in the bushes?). Chairgun is useful for seeing what parameters make a bigger difference, scope height is a big one but that shouldn't change! Pellet speed is not very sensitive it seems, assuming the regulator lives up to its name. BC is, rightly, a bigee and any time I see numbers quoted to 8 decimal places (hover the mouse over the BC box) it bothers me (I used to be a 'scientist' and did my A-levels and degree using a slide rule and 4-figure log tables! - good enough for NASA engineers hahaha).

BC is a mish-mash of a lot of variables and is possibly best described as a fudge-factor for air rifle pellets (bigger, better defined bullets are likely to be more consistent). What we really need is a fancy 3D laser measuring rig which gives some real numbers for the dimensions, weigh it to some reproducible standard (balance vs. a standard) and then bench test it indoors with a couple or more chronos. Failing that a couple of nice soft touch micrometer gauges.

I suspect you are right and that will eventually give you some multi-variate headache but a better understanding of what measurement is the one to go after or maybe two.

It would be a lot of fun to do that and then have some smoke streamer (wind tunnel like things) outdoors to show exactly what is blowing and which way or even decent wind meters and then put theory to test.

If I can help with a marathon day of measuring, weighing and testing let me know.

Alternatively we throw people who get 46+ on such days in to the fish ponds - if they float then they are witches.. :-)

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