Objective Handgun Round Evaluation Formula
Below is the OHREF Standard Calculator. If you’d like an in depth explanation of how it works and what went into the development of this standard you can read the full article here.
The calculator is currently in beta and may have some bugs present. If you have any feedback or encounter any bugs feel free to reach out on X @CapAndBallSEO.
How to Use
Enter the test results for the loading that you want to carry as well as other fields such as magazine capacity (of your loaded magazine and chambered round) and the total number of extra rounds carried.
Hit calculate and the tool will give you a total score and an individual breakdown of each factor.
For those that want to tinker under the hood, you can grab the raw alpha excel file used to create this here or the version that includes all of the Lucky Gunner test data as well.
Ballistics Performance Calculator
Tuning Variables & Complete OHREF Standards
Standards
- Minimum Penetration Accepted
- 13.5″ Inches
- OHREF Standard for Minimum Penetration
- Minimum Penetration to Score
- 12″ Inches
- FBI Ballistics Testing Minimum Penetration, anything below this is graded at a zero
- Maximum Penetration
- 24″ Inches
- Maximum Penetration allowed in the OHREF Standard, anything beyond this is graded at a zero
- Ideal Penetration Range Minimum
- 14″ Inches
- Ideal Penetration Range Maximum
- 19″ Inches
- Minimum Expansion Accepted Multiplier
- 1.2x
- Minimum Expansion over the starting diameter allowed in the OHREF Standard
- Minimum Accepted Retained Weight after firing
- 85% of original weight
- Failure to Pass Penalty Score Reduction
- 75% of score
- Ideal Expansion Diameter
- 0.5325″ Inches
- 1.5x a 9mm bullet diameter
- Idea Magazine Capacity
- 15 Rounds
- Equivalent to the standard capacity of a Glock G19 Pistol or similar.
Variables
These are the tuning variables used to control the influence of each element of the score so that no one element is over or under represented.
- Muzzle energy Tuning Variable
- 0.10
- Penetration Tuning Variable
- 0.4
- Expansion Tuning Variable
- 0.15
- Ammunition in Extra Magazines Penalty
- 0.25
- Extra Rounds Carried Tuning Variable
- 0.1
- Magazine Capacity Tuning Variable
- 0.4
- Weight Retention Tuning Variable
- 0.15
