MANUFACTURER – Military Armament Corporation (MAC), Marietta, Georgia
STATUS – Out of production
SERVICE – Limited US Military service, Secret Service and Special Operations Forces, Bolivia, Columbia, Guatemala, Honduras, Israel, Portugal, United Kingdom, Venezuela
The Ingram M10 submachinegun was the first US produced commercially successful design that could meet the idea of a Personal Defensive Weapon (PDW). Ingram’s intent for the very compact submachinegun was the idea that it would be particularly useful for clandestine or covert warfare. He wanted the weapon to be the lightest and most compact submachinegun of the time as well as being safe and easy to handle. The design was initially developed in 1964 and the first prototype was available in 1965. The first three prototypes were made in 9x19mm (2 specimens) and .45 ACP. The 9mm weapons used the Sten magazine, the 45 ACP the M3 Greasegun magazine. In 1967, Ingram had joined with the Sionics Company with his partner Mitchell L. Werbell III, who had a deep background with covert and intelligence agencies. Werbell had been manufacturing suppressors for the US Military and other sales. Sionics joined with the Military Armament Corporation (MAC) in 1970. It was very shortly after this that the Ingram submachinegun became known as the MAC-10.
The M10 submachinegun had a very short overall length while still retaining a reasonably barrel length. The short length was accomplished by Ingram using the telescoping bolt where the breech face itself was near the center of the bold body. The bolt otherwise surrounded the barrel on two sides with an additional mass at the rear. The recoil spring extended down a bored hole on the upper left inside of the bolt body. The body of the weapon was of formed sheet steel pieces assembled by heliarc welding. The M3 Greasegun magazine used with the weapon was very slightly modified from the original style to account for the magazine catch being at the rear of the magazine on the M10.
The central magazine well on the M10 was also the grip, allowing for the weapon to maintain balance while the magazine was being emptied. At the base of the stub barrel that extended from the front of the weapon was a coarse threaded section. This section was to allow the attachment of the Sionics-designed suppressor, intended to be used with the weapon. A sliding metal stock was part of the weapon. The stock folded over the rear of the M10 and could be removed easily by the operator for maximum concealability of the weapon. The cocking knob along the top of the weapon could be rotated to lock the bolt in the forward or cocked position. The center section of the cocking knob had a deep U machined into it. When the cocking knob was rotated and locked the bolt from moving, the solid side would block the shooter from seeing through the sights. When rotated for firing, the U notch allowed for an easy sight line.