MPBR Calculator: Maximum Point Blank Range

What is Maximum Point Blank Range (MPBR)?

Maximum Point Blank Range (MPBR) is the longest distance at which a shooter can aim directly at a target without needing to adjust for bullet drop. It represents the maximum range where the bullet’s trajectory stays within a specified vertical distance (usually the vital zone of the target) both above and below the line of sight. Understanding MPBR is crucial for hunters and shooters as it simplifies field shooting by eliminating the need for trajectory compensation within this range.

How to Calculate Maximum Point Blank Range

1. Determine your rifle’s muzzle velocity in feet per second (fps) from the ammunition manufacturer’s specifications or through chronograph testing.
2. Find the ballistic coefficient (BC) of your bullet from the manufacturer’s data. This number typically ranges from 0.2 to 0.6 for most hunting bullets.
3. Measure the sight height – the vertical distance between your rifle’s bore center and the center of your scope or sights, typically measured in inches.
4. Decide on your maximum acceptable rise, which is half the diameter of your target zone. For big game hunting, this is usually 3-4 inches.
5. Enter these values into their respective fields in the calculator.
6. Click the calculate button to get your MPBR and optimal zero range.
7. Review the results and explanation provided. The MPBR shows the maximum distance you can shoot without adjusting your aim, while the zero range indicates the optimal distance to zero your rifle.
8. Use this information to set up your rifle’s zero and determine your effective shooting range in the field.