Nicw find cranky! I guess that this is all softcore mode?
Most important bit i found was this.
On the "physics" of Bullet Drop, there are several types of bullets:
Bullet. The standard for all weapons from pistols to the weaker Recon Rifles. They are not affected by gravity at all. You can fire straight at an enemy at any distance.
Sniper_Bullet. A bullet affected by fake gravity. Used by the M24, SV-98, GOL, and Slug Shotguns
HMG_bullet. Used by stationary and vehicle mounted machineguns. That AND the M95 sniper rifle.