 Most Model 1927s owned by police have been converted back to full-auto.The original Model 1927 is classified as a machine gun under the National Firearms Act of 1934 (a) by being "readily convertible" by swapping parts and (b) by a 1982 BATF ruling making all open bolt semi-automatic firearms manufactured after the date of this ruling classified as machine guns.The Model 1927A1 is a semi-automatic replica version of the Thompson, originally produced by Auto-Ordnance of West Hurley, New York for the civilian collector's market from 1974 to 1999.