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Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Altitude vs. Barometric pressure
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<blockquote data-quote="rotorhead" data-source="post: 126016" data-attributes="member: 5078"><p>I'm not sure it this will help ,but in the world of aviation we use a standard day. This is a datum for figuring weather and performance. The pressure average is 29.92Hg at sealevel and temp of 15C or 59F The pressure lapse rate is 1" per 1000ft. The temperature lapse rate is 2 per 1000ft but the humitidy issue eirlier stated has a great effect on aircraft and a bullet in a sense is a aircraft like a rocket so to speak.In the big skeem of things Density is the controlling factor. The density of the air determines the performance. Example: Your are at 5048ft above sea-level the temperature is 5C under these conditions you are at standard day. The bullet will perfome as if you are at 5048 feet.if the temperature changes to 30C the bullet will perform as if it was at 7855 ft. conversley a temperature change to -25C the bullet would perform as if you were at 1232 ft. I have no idea if this helps but it may give you a standard to go off of.</p><p></p><p></p><p>RH</p></blockquote><p></p>
[QUOTE="rotorhead, post: 126016, member: 5078"] I'm not sure it this will help ,but in the world of aviation we use a standard day. This is a datum for figuring weather and performance. The pressure average is 29.92Hg at sealevel and temp of 15C or 59F The pressure lapse rate is 1" per 1000ft. The temperature lapse rate is 2 per 1000ft but the humitidy issue eirlier stated has a great effect on aircraft and a bullet in a sense is a aircraft like a rocket so to speak.In the big skeem of things Density is the controlling factor. The density of the air determines the performance. Example: Your are at 5048ft above sea-level the temperature is 5C under these conditions you are at standard day. The bullet will perfome as if you are at 5048 feet.if the temperature changes to 30C the bullet will perform as if it was at 7855 ft. conversley a temperature change to -25C the bullet would perform as if you were at 1232 ft. I have no idea if this helps but it may give you a standard to go off of. RH [/QUOTE]
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Rifles, Reloading, Optics, Equipment
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Altitude vs. Barometric pressure
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