01-05-2016, 05:02 PM
I played with the numbers in the JBM Ballistics Calculator and here is what I got. I input for a 6.5mm 129 Nosler Accubond Long Range (0.553 BC-Litz) and I made an educated guess for a 6.5 Grendel load at 2450 fps in a 20" barrel, 200-yd zero, wind 10mph, target speed 0, all other inputs default. I then bumped it to 2600 fps — increase of 150 fps — for a hypothetical, higher-pressure bolt-action load with all other inputs the same.
300-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 1.3", DRIFT = 0.3", VELOCITY = 134 fps
600-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 12.3", DRIFT = 2.6", VELOCITY = 116 fps (yes, the gap narrowed)
Only the shooter can say whether the differences are worth it to him.
Full charts attached below. OK, I see the charts imported at very low resolution, barely readable. Anyway, you get my drift. . . .
300-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 1.3", DRIFT = 0.3", VELOCITY = 134 fps
600-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 12.3", DRIFT = 2.6", VELOCITY = 116 fps (yes, the gap narrowed)
Only the shooter can say whether the differences are worth it to him.
Full charts attached below. OK, I see the charts imported at very low resolution, barely readable. Anyway, you get my drift. . . .
:: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets
:: I Drank the Water :: Revelation 21:6 ::
:: I Drank the Water :: Revelation 21:6 ::