I found a good load with the 195g Hybrids and H4831SC in my .284 Win fclass rifle. I was considering shooting that combination in my next LR match, so wanted to do some ballistics calculations to help with my range card and sighters. I was surprised with my findings.
Looking at the Berger twist rate calculator, I inputted my information (2700fps/9 twist/59 degrees/800 ft/1.640") and got the corrected BC (after the 6% decrease due to the SG of 1.29) of 0.363 G7. Knowing that the G7 BC of the 180g Hybrid is 0.345 I then put both into the JBM calculator at my node's velocites of 2700 for the 195s and 2820 for the 180s.
The 195s had a drop from a 100y zero to 1000 yards of 28.5 MOA with 5.5 MOA of drift for a 10 mph 90 degree drift. Conversely, the 180s neede 26.5 MOA up and had 5.5 MOA of wind.
Therefore, in a 1:9 twist barrel at the velocity of the nodes that I shoot, the 195g Hybrids are no better in the wind for my application.
Now to buy a 1:8.25 twist barrel for the 195s and extended my FB for the 195s and get them hammering. I love projects!
Looking at the Berger twist rate calculator, I inputted my information (2700fps/9 twist/59 degrees/800 ft/1.640") and got the corrected BC (after the 6% decrease due to the SG of 1.29) of 0.363 G7. Knowing that the G7 BC of the 180g Hybrid is 0.345 I then put both into the JBM calculator at my node's velocites of 2700 for the 195s and 2820 for the 180s.
The 195s had a drop from a 100y zero to 1000 yards of 28.5 MOA with 5.5 MOA of drift for a 10 mph 90 degree drift. Conversely, the 180s neede 26.5 MOA up and had 5.5 MOA of wind.
Therefore, in a 1:9 twist barrel at the velocity of the nodes that I shoot, the 195g Hybrids are no better in the wind for my application.
Now to buy a 1:8.25 twist barrel for the 195s and extended my FB for the 195s and get them hammering. I love projects!