BHN, What Does It Stand For, And What Does It Mean To Shooters/Handloaders?
:: By on 2001-01-29 Print This FAQ | Share This FAQ Brinnell Harness Number, or BHN as it is abbreviated, is a relative hardness scale. The numbers are derived from the load bearing ability of of a sample in terms of Kilograms (Kg) supported by one square millimeter (mm). This scale is mathematically progressive, in that tripling the BHN number, triples the sample hardness. Conversely, if you cut the BHN number in half, the hardness of the sample is half that of the original. OK, what does that mean to the shooter and handloader? It is the most common measurement of hardness that is applied to projectiles. Here are some common examples: Bullet Alloy BHN Pure Lead 5 1:20 Tin-Lead 10 Wheel Weight 11 1:10 Tin-Lead 11 Lyman #2 Bullet Alloy 15 Linotype 22 Pure Copper 40 Now, since the relative BHN of an alloy can be definitively determined, it also stands to reason that the amount of force necessary to deform, or obturate the sample in question also may be calculated very precisely as well.
