Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Firearms Publications

ATF occasionally issues publications to inform the industries it regulates and the general public about the laws and regulations administered and enforced by ATF. These include guidebooks, newsletters, brochures, studies, and reports.

Search by title or description

Document Type

Document type Title and Description

Regulatory

Document type	Title and Description
Regulatory	1957-34 - Classification of 4-inch Diameter Barrel Extension [PDF - 230.15 KB] Classification of a 4-inch diameter barrel extension Published/Revised: January 1, 1957

1957-34 - Classification of 4-inch Diameter Barrel Extension [PDF - 230.15 KB]

Classification of a 4-inch diameter barrel extension

Published/Revised: January 1, 1957