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Old 10-13-2012, 11:44   #31
Big Bird
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Originally Posted by TheBelly View Post
Paraphrashing what big bird wrote:

Load development has a large role to play in where (along the flight path) a bullet will go into the subsonic speeds. BC of the projectile gets a vote here.

Environmental (particularly the density altitude and wind conditions) can wreak havoc on your attempts... Ballistic solvers are all well and good, but the bullet really tells you what's going on.

True the ballistic solver and then you have the no-crap answer as to what is happening between the internal and external ballistics of your rifle/bullet combo.
Its also been my experience in working up 1,000 yard loads that standard deviation means a lot in terms of accuracy. You take a .308 load of most any flavor with a standard deviation of between 30 and 40 FPS and you have a built in 1-1.5 MOA dispersion factor at 1,000 yards added to the mechanical accuracy of the platform. That's 10-12" load to load vertical dispersion on the target based solely on small velocity changes. I always tried to get my long range loads down to under 10 FPS Standard Deviation.
Big Bird,

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