The weapons use damage profiles (Rifle, Carbine, Assault Rifle, SMG, LMG) to get their general role, and tweak it from there. There are 3 range values that are used to adjust the damage curve, Near, Mid, and Long. These values are set between a Minimum and Maximum range. For example,
Obersoldaten's "Near" range is 0, "Mid" is 25, and "Far" is 35. If a distance between Near is higher than the Minimum, it'll have flat DPS with no change. Same with Long and Maximum, but Near/Min is the one that's important because of how SMG's are set up. For the
Shock Troop PPSh, "Near" is 10, "Mid" is 16, and "Far" is 30, so the points between 0-10 and 30-35 are just flat DPS. Between 1-10 is where a Submachine Gun wants to be 100% of the time.
As a general rule of thumb, you can consider Near as 0 - 10, Mid as 10-20, and Long as 25-35. This is usually where the values sit, but it varies from weapon to weapon. 1/3 of your unit's line of sight is about 11 - 12. For perspective these pictures might help. The short lines indicates 5s, long indicates 10s.
