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Old 07-18-2019, 10:00 PM
mmartin798 mmartin798 is online now
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Quote:
Originally Posted by Desert Mariner View Post
The actual coefficients are normally listed on the box and/or in the manufacturer's literature. I started a similar exercise not too long ago and the first decision to be made is what specific cartridges to use. I ended up using cartridges from Sellier & Bellot (S&B) since they didn't have an overwhelming number and they provide the needed info (BC, V0 with test barrel length, projectile weight, etc.). Even this small selection provided 6 normal 9mm loads plus 2 subsonic 9s. I then computed the MV for each weapon with the selected cartridge. Picked an on-line calculator (Berger Bullets as it is simple) and set up an Excel sheet to import the generated data. The attached PDF is what I generated for 4E weapons (shotguns are not included as I'll need separate range charts for slug and shot).

Range cards for pistols run 10-200m at 10m increments, sub guns run 20-400m at 20m increments and rifles/MGs run 50-1000m at 50m increments. Some of these probably need adjustment. E-factor for each range is calculated from the listed velocity for the range. Cartridge used is listed on the range card as well so that anyone can recreate a chart at different ranges if they so desire.

I'm currently giving the same treatment to some updated weaponry but there doesn't seem to be much interest in the other thread I posted in.
I just want to point out that in the Berger Bullets ballistics calcultator, you still need to select the curve set. Looking at the presets, the pistol rounds use G1 and the rifle rounds use G7.
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