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Hunting
The Basics, Starting Out
Long range hunting comes down to 2 separate things wind and flight time
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<blockquote data-quote="brant89" data-source="post: 2619520" data-attributes="member: 49553"><p>Yes, wind drift is directly related to lag time and not TOF, and yes total drag is INCREASING with increased velocity, but the coefficient of drag (Cd) is DECREASING with an increase in velocity, which is why we see BC increase with an increased velocity. For the math nerds out there, the formula for CD illustrates why an increase in velocity results in a decreased Cd (velocity is squared in the denominator):</p><p></p><p>Cd = D / (A * .5 * r * V^2)</p><p></p><p></p><p>Here's a couple different ways to think about it:</p><p></p><p>First, lets pretend we have a hypothetical bullet that has a G1 BC of .550 above 2800fps, and a G1 BC of .500 below 2800fps, and the change in BC is abrupt (i.e. it is .550 @ 2800fps and .500 @2799fps). you can basically treat this bullet as two COMPLETELY different projectiles in these two different velocity brackets, and I think we can all agree that the one with the higher BC will necessarily experience less wind drift. So even if the velocity drops below 2800fps at some point in the bullets flight, it still experienced wind drift at the higher BC value for the portion of its flight that it was above the 2800fps threshold and would thus experience less wind drift during that portion of its flight time, which would ultimately lead to less wind drift over the entirety of its flight as well. Obviously this is an exaggerated example, but it serves to illustrate the concept.</p><p></p><p>Another way to illustrate it is to think of the bullet as a weather vane that always points directly into the resulting wind vector, which is a product of both the bullets forward velocity and crosswind component, and the bullet drag vector is parallel to the resulting wind vector. Therefore, anything we can do to decrease the angle of the resulting wind vector in relation to the line of sight will also decrease wind deflection. Given the same exact bullet, the only two ways this is possible is to either decrease the crosswind speed or INCREASE the forward velocity. This is again an oversimplification, but serves to illustrate the concept.</p></blockquote><p></p>
[QUOTE="brant89, post: 2619520, member: 49553"] Yes, wind drift is directly related to lag time and not TOF, and yes total drag is INCREASING with increased velocity, but the coefficient of drag (Cd) is DECREASING with an increase in velocity, which is why we see BC increase with an increased velocity. For the math nerds out there, the formula for CD illustrates why an increase in velocity results in a decreased Cd (velocity is squared in the denominator): Cd = D / (A * .5 * r * V^2) Here's a couple different ways to think about it: First, lets pretend we have a hypothetical bullet that has a G1 BC of .550 above 2800fps, and a G1 BC of .500 below 2800fps, and the change in BC is abrupt (i.e. it is .550 @ 2800fps and .500 @2799fps). you can basically treat this bullet as two COMPLETELY different projectiles in these two different velocity brackets, and I think we can all agree that the one with the higher BC will necessarily experience less wind drift. So even if the velocity drops below 2800fps at some point in the bullets flight, it still experienced wind drift at the higher BC value for the portion of its flight that it was above the 2800fps threshold and would thus experience less wind drift during that portion of its flight time, which would ultimately lead to less wind drift over the entirety of its flight as well. Obviously this is an exaggerated example, but it serves to illustrate the concept. Another way to illustrate it is to think of the bullet as a weather vane that always points directly into the resulting wind vector, which is a product of both the bullets forward velocity and crosswind component, and the bullet drag vector is parallel to the resulting wind vector. Therefore, anything we can do to decrease the angle of the resulting wind vector in relation to the line of sight will also decrease wind deflection. Given the same exact bullet, the only two ways this is possible is to either decrease the crosswind speed or INCREASE the forward velocity. This is again an oversimplification, but serves to illustrate the concept. [/QUOTE]
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Hunting
The Basics, Starting Out
Long range hunting comes down to 2 separate things wind and flight time
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