During the 1970s, the United States placed restrictions on the export of suppressors, and a number of countries canceled their orders as the effectiveness of the MAC-10's suppressor was one of its main selling points. The suppressor, when used with a Nomex cover, creates a place to hold the firearm with the secondary hand, making it easier to control. It is also very quiet, to the point that the bolt can be heard cycling, along with the suppressed report of the weapon's discharge, though only if subsonic rounds are used (standard. This uniquely shaped suppressor gives the MAC-10 a very distinctive look. This suppressor has a two-stage design, with the first stage being larger than the second. The primary reason for the original M10 finding recognition was its revolutionary sound suppressor designed by Mitchell WerBell III of Sionics. Noting the weapon's poor precision, in the 1970s, International Association of Police Chiefs weapons researcher David Steele described the MAC series as 'fit only for combat in a phone booth'. That of the 9mm is approximately 1250, and that of the smaller MAC-11 in.

45 ACP is approximately 1090 rounds per minute. The original rate of fire for the MAC-10 in. Ingram added a small bracket with a small strap beneath the muzzle to aid in controlling recoil during fully automatic fire. At the suggestion of the United States Army, the suppressor also acts as a foregrip to inhibit muzzle rise when fired. 45 ACP versions, as most loads are subsonic already, as opposed to special, low-powered subsonic loads usually required for suppressed 9mm weapons. The barrel is threaded to accept a suppressor, which works by reducing the discharge's sound without attempting to reduce the speed of the bullet. In addition, this design incorporates a built in feed ramp as part of the trigger guard (a new concept at the time) and, to save on cost, the magazine was recycled from the M3 Grease Gun.

The MAC-10 fires from an open bolt, and the light weight of the bolt results in a rapid rate of fire. This allows a more compact weapon and balances the weight of the weapon over the pistol grip, where the magazine is located. The MAC-10 has a telescoping bolt, which wraps around the rear face of the barrel. A notched cocking handle protrudes from the top of the receiver, and turning the handle 90°, locks the bolt, and acts as an indicator the weapon is unable to fire.

The MAC-10 is built predominantly from steel stampings.

Mac 10 receiver for sale