Large-Format Pistols

A large-format pistol is built on a rifle or carbine action but has no stock, which keeps it legally a pistol despite looking nothing like one. AR and AK-pattern pistols and pistol-calibre carbine variants are the common examples, and they exist to give rifle ergonomics in a package that is not a short-barreled rifle.

This is the category where the configuration is the legal question. A stabilising brace, its attachment, and what happens when a stock is fitted instead have all been the subject of shifting federal rulemaking and litigation. If you want the stocked version, the clean answer is an SBR on a Form 4 — and since January 2026 the tax stamp for that is $0.