A firearm, in particular handgun, has a barrel mechanism with a barrel and a chamber, a closing mechanism with a slide and also a cylinder-piston mechanism for gas pressure-operated closure delay. The cylinder-piston mechanism has a hollow cylinder with a hollow cylinder wall. A channel is formed between the barrel mechanism and the cylinder-piston mechanism. The hollow cylinder wall is fitted with at least one reinforcing element. The firearm may be produced by the following process steps: introduction of a first portion of the bore into the basic body up to the recess; introduction of a second portion of the bore up to the hollow cylinder; drilling of the channel, wherein the drill is conducted through the bore; and introduction of the reinforcing element into the recess, wherein the bore is closed in a gas-tight manner.