How does a firearm function?

There is some casual dispute over the correct use of the words automatic and semi-automatic. Gun enthusiasts sometimes argue that the word automatic is incorrectly linked to fully automatic fire and that an automatic weapon is simply any weapon that chambers a new round during the extraction of the previous cartridge's casing. The term is often used to mean a self-loading semi-automatic firearm rather than a fully automatic one. One narrow definition would be that a semi-automatic firearm would thus be a weapon using the open bolt system, and the semi-automatic function is simply the removal of the case, whereas an automatic weapon would both remove the empty case and chamber a fresh cartridge. In practice, an automatic pistol usually means a self-loading semi-automatic pistol but an automatic rifle usually means one capable of fully automatic fire. Both uses can be found, and the exact meaning must be determined from context. Among U.S. law enforcement practitioners, amongst whom the use of double-action revolvers has almost entirely disappeared, the term "automatic pistol" has been supplanted by the jargon term "auto-loader".