Non-Blowback (NBB)

Where a blowback pistol spends part of every shot's gas pressure driving the slide rearward, a non-blowback design routes all of it into launching the BB. The slide is fixed or purely cosmetic, so there is no reciprocating mass, no recoil spring wear and no slide-related jams.

That efficiency means more shots per gas fill and a mechanism simple enough to survive rough handling, which is why NBB pistols are common as budget backups and as the mechanism behind many green gas revolvers. What they give up is the visual and tactile feedback of a cycling slide that blowback shooters buy GBB pistols for in the first place.

Because there's no slide mass to cycle, an NBB pistol is also noticeably quieter to fire than a blowback one, which some CQB and stealth-focused players actually prefer over the louder mechanical clack of a slide.