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I'd like to report a curiosity: the actual trajectory of my handload was significantly different from the calculated value. 257 R, Sierra 117 Sp (BC = 0.403), MV 2650fps from a chronograph.
Specifically, I have a Savage M110 from their Custom Shop (walnut stock and blue bbl) chambered in 257 Roberts. It shoots very well. I zeroed at 200 yards (two shots one inch apart, dead on), then moved to my 100 yard range and fired two more rounds - two shots touching, but 3 3/4 inches high! Three different ballistic calculators predict the bullet to be 2.2 inches high at 100, if zeroed at 200. I fully agree that the difference is insignificant in a hunting scenario confined to these ranges. I simply want to suggest that ballistic calculators are great tools, but they should be confirmed by actually putting a bullet downrange.
 

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Some ballistic calculators leave a lot to be desired. They don't take into account barometric pressure, altitude, temperature, and other environmental elements.

You also have to take into consideration the human factor. The difference of an inch could have easily been the nut behind the trigger.
 

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You also have to account on the bullet companies stretching the truth on the BC numbers on some of their stuff,and also correctly inputting info on the ballistic calculator.

JBM has several different programs you can use,it all depends on how much information you want to input on each one. Shooting out to a mile,I've never been off more than a couple clicks unless it was real windy.
http://www.jbmballistics.com/ballistics/calculators/calculators.shtml
 
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