Posted: 8/11/2011 12:49:31 PM EDT
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I need to know .308 bullet performance at 100, 200, 300yrds ect. anyone help me out?
Just basic performance rise and drop at the yardage. I am shooting factory loads. Federal I believe 165gr ammo. |
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Right here on Federal's website:
Federal .308 165gr ballistics |
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You do need to run them through a chrony for your gun. Once you have that:
JBM Trejectory Calc |
If you use a 1/4 moa scope then multiply come up by 4.
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Quoted:
You do need to run them through a chrony for your gun. Once you have that: JBM Trejectory Calc The speed can be estimated without a chronograph, but it requires shooting at a target and use of a ballistics program to back out the speed required. Get a good zero on the rifle, say at 200 yards. Apply the come ups required for 600 yards (for example), shoot the target, and then compare the actual vertical displacement on the target to that predicted by the program. Run the ballistics program with the zero set at 600 yards for this example to find the trajectory at 200 yards, then compare the numbers. Leave the BC in the program alone, we're trying to get an estimate of the muzzle velocity. This is not strictly correct, but computing actual BC is way more complicated and the speeds must be known, and this method will work as the published BC's are very close to the actual number in the field, plus the results are terribly sensitive to BC, especially when the goal is to get the first shot on target. This isn't a bad double check to perform before taking the next shot at 600 yards, even if the muzzle velocity has been measured. |