A rifle has a fixed main body including a barrel, a receiver with an upper opening, and a breech element. A carriage assembly is axially movable between an advanced shooting configuration and a retracted rearming configuration, and vice versa. The carriage assembly includes an assembly body positioned on the receiver at the upper opening, which is axially slidably movable, having a through housing extending transversally, a firearm handle with an outer portion grippable and an inner portion shaped for complementarily housing in the through housing, being insertable both sides, and a shutter group partially accommodated in the assembly body, including a shutter body and a shutter head. The shutter head is mountable onto the shutter body in first and second angular positions, which are reciprocally inverted. The rifle is configurable for a right-handed or a left-handed person by changing the position of the firearm handle and the shutter head.