Before he made a big success with the M10 (MAC-10) submachine gun, Gordon Ingram designed a couple other guns. His initial M5 submachine gun and M20 light machine gun never went past prototype stage, but the M6 did prove to be successful, at least in a limited way. The M6 was a very simple blowback .45ACP submachine gun very deliberately made to look like the Thompson. It was introduced in 1948, and in 1949 Ingram and other investors created the Police Ordnance Company to market and sell it. A total of about 2,000 were made, including an order of 400 to the Peruvian government which was coupled with a licensing agreement which would see some 8,000 more produced in Peru on license.

The Model 6 was offered in three calibers, but only the .45 ACP saw any sales (the other options were 9x19mm and .38 Super). Three configurations were detailed in the company’s marketing literature, although in production guns some of the features were mixed. The official models were the Police (finned barrel and vertical front grip), Guard (smooth barrel and horizontal front grip), and Military (smooth barrel, fully hooded sight, sling swivels, and spike bayonet). Production on lasted for a few years, as Ingram left the company in 1953 and it dissolved in 1954. Today, Model 6 submachine guns are a neat and under recognized piece of Ingram history, completely overshadowed by the M9, M10, and M11 designs which Ingram would produce later.