"Round nose of all of these calibers wont make much diference if you cant shoot sub ammo past 300 yards."
Drop is 192 ( t) ^2 inches where t is the time of flight in seconds for any bullet at any
velocity. Higher muzzle velocity and higher both BC reduces time of flight. The drop due to gravity is quite predictable. Muzzle velocity is the most important variable and with good loading technique it's variability can be held in the order of 1%.
For a muzzle velocity of 1000 fps bullet drop at 300 yards is aout 171.5" for a BC of 0.4 and 164.2" for a 0.8 BC. The vertical stringing for a 1% velocty variation is about 3 inches.
At 600 yards the drop is about four times more, 745.2" for a 0.4 BC and 685.8" for a 0.8 BC. the vertical dispersion for a 1% velocity variation is 12.9" for a 0.4 BC and 11.9" for a 0.8 BC. Going from .4 to .8 BC has an advantage at practical ranges, but not a lot unless the BC is less than 0.4.
700 inches of drop at 600 yard is "only" 100 MOA from a 100 yard zero. Personally I consider 600 yards, not 300 as the practical range limit for a good quality subsonic rifle assuming you can accept a 12" diameter group for a 1% velocity spread. The actual group size is dependent on how low of velocity spread can be achieved in the ammo. Benchrest loadnig techniques are a necessity. At that range an accurate rangefinder and target knobs are also essential. The bigger calibers with similar BCs but heaver bullets simply deliver more energy. They have little effect on accuracy which is still dependent mosty on velocty dispersion and to a lesser extent on wind deflection.
Last edited by LouBoyd; 12-21-2008 at 05:14 AM.
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