at the beginning of next game level on single player i started with: Sniper rifle, SCARAB and Hammer pistol. at first i thought it was unlocked in-game feature but later i realised that scarab got totally bugged and when i look at it i see 40 / -120 ammo. For some time i didn't use SCAR or SCARAB because every new one i pick up starts with 40/-120 ammo and using resuply box makes it go to 40/0 (and then it shows "Full ammo"). now it moved to shotgun and sniper rifle. (but at the begining on another level it reseted and got me worried cause i don't want to use Hammer all the time instead of SCAR )