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Old 29th May 2012, 02:42 PM
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RobF RobF is offline
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Member of: Southampton Buccaneers, Parkstone, South Dorset
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Originally Posted by NJR 100 View Post
Hi Rob now i know you were very kindly trying to explain this thing to me Sunday, but your words had more than 4 letters so i was a bit lost.

Is the basics of what your saying this.

Warm day / warm air, pellets fly flatter further out but not effected closer in?

If so, it matches my results Sunday as i had three go high. Gun was set up recently but probably about 15 degrees where as Sunday was 25+ . I too was high on the chrono when i tested before starting, running 791 - 793. so i turned the REV down to 785 ish.
Close ranges were not effected

But on a cooler / cold day you may expect the pellet to slow more so it may drop slightly more?

Hence the normal Summer and winter set ups?

So in effect next time we have a shoot in very warm conditions (20+ ??), i may want to take a couplke of clicks off past 40m
Erm... yes, and no.

Mostly yes.

The air gets thinner and pellet flys flatter... the air gets thicker and it drops more. We first saw this to a big degree in SA.

The catch is that the density of air is actually a combination of temperature, humidity and air pressure. Not just hot and cold, or damp or dry. And these factors can cross over or cancel each other out depending on what they are. Typical eh! The machine works it out and gives you a figure which allows you to see a clear relationship. Couple that with any notes on POI, and you can see a trend. It's early days but it appears there is a clear one to me. I'd like to get more scientific and see if it can make a preditiction that can be tested.

So as well as scopes moving, the enviroment seemingly has an effect as well. As Alan says, it might well be that if a bit of kit moves the other way, it could really minimise it... hence someone saying "nah i made it 50 and i hit it dead centre"... it actually being 55 but the scope moved but the pellet flew flatter. You can also add into that mix guns running faster/slower!

Keeping an eye on it over the past 6 months kind of answers why some people see shift but miss, some see it but hit and also why some may have shift but never notice it because of a combination that means there's little effect." The target went over didn't it?!" All that counts, but like I said to Andy on the line, i'm interested as to why it does it. If anything, at the moment, it gives me another excuse.
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