My first LEGO Technic Moc. It's supposed to be a sniper rifle! It isn't able to shot or anything, but it does have som features like a trigger and a reloading system! :
LEGO MOC Anti-Aircraft Gun by kueden | Rebrickable - Build with LEGO
LEGO MOC Lego Select Fire Blowback Rubber Band Pistol. by Wild Cat | Rebrickable - Build with LEGO