Making a pocket field card for a specific load and bullet will aid in improved vital zone bullet placement.
The card is really a drop or trajectory table with wind and energy at a specific laser rangefinder game distances your looking to shoot.
I used my Nosler 300g AccuBond to create the table below for my moose hunt with the .375 Ruger. There are many ballistic calculators on the market. I use JBM Ballistics Trajectory calculator (free on-line). It works great!!
The pocket card you take into the field will look like the card above. Wind drift is in inches with a 10 mph 90 degree crosswind. I zeroed for 250 yards. Go to the website below and experiment.
https://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi
You can select your bullet from this software’s drop down menu, enter the bullet muzzle velocity, zero-range, wind, elevation, vital-zone radius and many other parameters for the table you will create.
| Trajectory | |||
| Input Data | |||
| Manufacturer: | Nosler | Description: | Accubond™ Spitzer |
| Caliber: | 0.375 in | Weight: | 300.0 gr |
| Ballistic Coefficient: | 0.473 G1 (ASM) | ||
| Muzzle Velocity: | 2550.0 ft/s | Distance to Chronograph: | 10.0 ft |
| Sight Height: | 1.50 in | Sight Offset: | 0.00 in |
| Zero Height: | 0.00 in | Zero Offset: | 0.00 in |
| Windage: | 0.000 MOA | Elevation: | 0.000 MOA |
| Line Of Sight Angle: | 0.0 deg | Cant Angle: | 0.0 deg |
| Wind Speed: | 10.0 mph | Wind Angle: | 90.0 deg |
| Target Speed: | 0.0 mph | Target Angle: | 90.0 deg |
| Target Height: | 40.0 in | ||
| Temperature: | 40.0 °F | Pressure: | 29.92 in Hg |
| Humidity: | 50 % | Altitude: | 0.0 ft |
| Vital Zone Radius: | 5.0 in | ||
| Std. Atmosphere at Altitude: | No | Pressure is Corrected: | Yes |
| Zero at Max. Point Blank Range: | No | Target Relative Drops: | Yes |
| Mark Sound Barrier Crossing: | No | Include Extra Rows: | No |
| Column 1 Units: | 1.00 in | Column 2 Units: | 1.00 MOA |
| Round Output to Whole Numbers: | No | ||
| Output Data | |||
| Elevation: | 7.540 MOA | Windage: | 0.000 MOA |
| Atmospheric Density: | 0.07925 lb/ft³ | Speed of Sound: | 1095.8 ft/s |
| Maximum PBR: | 302 yd | Maximum PBR Zero: | 255 yd |
| Range of Maximum Height: | 136 yd | Energy at Maximum PBR: | 2658.9 ft•lbs |
| Sectional Density: | 0.305 lb/in² | ||
I found that my rifle zero is best set for 250 yards as it allows for max point blank range with a vital zone radius for moose at 5 inches. Basically the size of a ten inch pie plate.
Here is a printout of the calculation.
| Calculated Table | ||||||||||
| Range | Drop | Drop | Windage | Windage | Velocity | Mach | Energy | Time | Lead | Lead |
|---|---|---|---|---|---|---|---|---|---|---|
| (yd) | (in) | (MOA) | (in) | (MOA) | (ft/s) | (none) | (ft•lbs) | (s) | (in) | (MOA) |
| 0 | -0.7 | *** | 0.0 | *** | 2556.6 | 2.333 | 4353.2 | 0.000 | 0.0 | *** |
| 25 | 1.1 | 4.2 | 0.1 | 0.2 | 2507.4 | 2.288 | 4187.4 | 0.030 | 0.0 | 0.0 |
| 50 | 2.6 | 4.9 | 0.2 | 0.4 | 2458.8 | 2.244 | 4026.5 | 0.060 | 0.0 | 0.0 |
| 75 | 3.7 | 4.7 | 0.5 | 0.6 | 2410.7 | 2.200 | 3870.6 | 0.091 | 0.0 | 0.0 |
| 100 | 4.4 | 4.2 | 0.8 | 0.8 | 2363.2 | 2.157 | 3719.4 | 0.122 | 0.0 | 0.0 |
| 125 | 4.7 | 3.6 | 1.3 | 1.0 | 2316.1 | 2.114 | 3572.9 | 0.154 | 0.0 | 0.0 |
| 150 | 4.7 | 3.0 | 1.9 | 1.2 | 2269.6 | 2.071 | 3430.8 | 0.187 | 0.0 | 0.0 |
| 175 | 4.2 | 2.3 | 2.6 | 1.4 | 2223.7 | 2.029 | 3293.2 | 0.220 | 0.0 | 0.0 |
| 200 | 3.2 | 1.6 | 3.4 | 1.6 | 2178.2 | 1.988 | 3159.9 | 0.254 | 0.0 | 0.0 |
| 225 | 1.9 | 0.8 | 4.4 | 1.9 | 2133.2 | 1.947 | 3030.8 | 0.289 | 0.0 | 0.0 |
| 250 | -0.0 | -0.0 | 5.5 | 2.1 | 2088.8 | 1.906 | 2905.8 | 0.325 | 0.0 | 0.0 |
| 275 | -2.4 | -0.8 | 6.7 | 2.3 | 2044.9 | 1.866 | 2784.9 | 0.361 | 0.0 | 0.0 |
| 300 | -5.2 | -1.7 | 8.1 | 2.6 | 2001.5 | 1.826 | 2668.1 | 0.398 | 0.0 | 0.0 |
| 325 | -8.7 | -2.5 | 9.6 | 2.8 | 1958.7 | 1.787 | 2555.1 | 0.436 | 0.0 | 0.0 |
| 350 | -12.7 | -3.5 | 11.2 | 3.1 | 1916.4 | 1.749 | 2446.0 | 0.475 | 0.0 | 0.0 |
| 375 | -17.2 | -4.4 | 13.0 | 3.3 | 1874.7 | 1.711 | 2340.7 | 0.514 | 0.0 | 0.0 |
| 400 | -22.4 | -5.4 | 15.0 | 3.6 | 1833.6 | 1.673 | 2239.2 | 0.555 | 0.0 | 0.0 |
| 425 | -28.3 | -6.4 | 17.1 | 3.8 | 1793.1 | 1.636 | 2141.3 | 0.596 | 0.0 | 0.0 |
| 450 | -34.8 | -7.4 | 19.4 | 4.1 | 1753.2 | 1.600 | 2047.1 | 0.638 | 0.0 | 0.0 |
| 475 | -42.0 | -8.4 | 21.8 | 4.4 | 1713.9 | 1.564 | 1956.4 | 0.682 | 0.0 | 0.0 |
| 500 | -50.0 | -9.5 | 24.5 | 4.7 | 1675.3 | 1.529 | 1869.3 | 0.726 | 0.0 | 0.0 |
| 13-Oct-22 13:46, JBM/jbmtraj-5.1.cgi |
By experimenting with muzzle velocity, wind, altitude parameters in the JBM software, you will better understand how your bullet will perform as it speeds its way to the intended game.
Good shooting!
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