Mild steel penetration model

[scriptguru]

I've found this formula it in the Quantitative Ammunition Selection book, and made a spreadsheet out of it.
Not sure how accurate it is, but seems to be good enough. It should work for handgun ammo only, I think.

Here is the link (just download the document and try different parameters)

Some results from this model, made for popular calibers:
TT-33 pistol (7.62mm 5.5g bullet @ 502 m/s) 5.73mm penetration
9x19 Para (.355in 124gr bullet @ 360m/s) 2.96mm penetration
.45 ACP (.452in 230gr bullet @ 830fps) 1.51mm penetration

 

[BCRider]

You didn't mention what thickness of steel. For 9 and .45 there is no penetration for 3/8 and thicker from what I've seen. And even for thinner metal it doesn't penetrate as much as it simply dishes back the metal.

 

[josquin]

You didn't mention what thickness of steel. For 9 and .45 there is no penetration for 3/8 and thicker from what I've seen. And even for thinner metal it doesn't penetrate as much as it simply dishes back the metal.

I have commercially-made (Quality Targets in IL, NRA-rated) 3/8" steel targets made from A36 and my 9mm and .45 hard-cast lead create a bit of minor cratering but nothing serious.

Nearly 3mm penetration from a 9mm Parabellum round? I wonder what kind of bullet they were using?

 

[scriptguru]

You didn't mention what thickness of steel. For 9 and .45 there is no penetration for 3/8 and thicker from what I've seen. And even for thinner metal it doesn't penetrate as much as it simply dishes back the metal.

The model is created to calculate the maximum thickness of a sheet of cold rolled mild steel certain bullet can penetrate.
I think it's made for FMJ ball ammo. You just need to enter bullet velocity, mass and diameter, and spreadsheet will calculate the maximum thickness of steel this bullet can penetrate.