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Old 2nd December 2009, 11:25 AM
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RobF RobF is offline
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I didn't check with everyone, but I think everyone I spoke to from the UK saw their POI rise in SA, and in fact it was a flatter trajectory... although the 25-30 didn't move, the far 55 yds saw around 1 MOA of rise, suggesting the pellet was flying flatter... which makes sense as the air at 4000ft is thinner... chairgun points to this but suggests less of a rise, however I didn't measure the humidity here and there

Certainly cold air is denser than warm, something that engine tuners and pilots know.

Humid air is less dense than dry air though... somewhere they probably cross over, but I don't know how to work that out unless someone has made a table up of air pressure vs humidity

So it would seem that perhaps temperature is not the key, but more air density. (i can hear all those ghosts of past days talking about falling shots over ponds... and I've seen shots rise really high low over the grass at Sywell in the heat, enough to take me and Neil Daniels out of a 40-45 yd kill in zero wind... and the rest of the course judging by the group of misses)

So the biggest drops would seem to be at sea level with cold hard frost sunny days in winter, and the biggest rise would perhaps be those humid hot sunny days... kind of bears fruit with my experiences.
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