Wow, thats..thats..something..
I hope this helps you understand.
I'm sorry, but no
This code basically means this:
The minimum damage you do, is:
minimum damage of the weapon * damage adjustment of the ammo * nerf
The maximum is similarly:
maximum damage of the weapon * damage adjustment of the ammo * nerf
Nerf is calculated in 3 steps.
1. Total DR of your target + DR from your ammo
2. If you have finesse, add 30
3. If this is already greater than 90, then you set the value of nerf to 0.1. Otherwise:
nerf = 1 - (DR of target + DR of ammo + 30 if you have finesse or 0 if not)/100
As you know, ammo has its own DR modifiers: it can add or subtract DR. The damage adjustment is that "2/1" ratio on 10mm jhp for one example.