Magazine interchange

[Tom-ADC]

Do Ingram MAC 10 45 ACP magazine interchange with a Thompson?

[fal_762x51]

I believe that the MAC 10 uses the M3 grease gun magazine.

[wilit]

No they do not interchange.

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[Tom-ADC]

I seem to remember the M3 interchange now, wanted to send this to a member for a Thompson rebuild.
Thanks

[Quiet]

The Ingram/MAC/SWD/Cobray M-10 in .45ACP was designed to use M-3 "grease gun" magazines, which are not compatible with Thompson magazines.

[Marcus von W.]

I have 2 MAC 10 .45 caliber pistols - an original Military Armaments Corp. production gun made in Stephenville, Texas and one of the new Masterpiece Arms guns. Both use the M3 grease gun magazine, which is totally different from the Thompson magazine.

The Military Armaments Corp. pistol uses a grease gun mag that has been slightly modified - about 1/16 inch milled off the area on the back where the mag catch locks in, and the same amount milled off the top of the "bumps" on each side. I've been told that replacing the mag catch with a later design one will allow the use of unmodified grease gun magazines.

The Masterpiece Arms gun uses standard unmodified grease gun magazines.

I notice that magazines inserted in the MPA gun have a little more wobble to them than mags in the MAC gun. I bought the MPA gun as a "single shot exemption" item with the black plastic "mag well butt-plug" so I don't have an MPA mag to compare, but looking at the photos of the magazines on the MPA website it seems that they are made slightly different than original grease gun mags, so perhaps the MPA mag well intentionally has just a little more clearance for their mags. It's not real bad and a loaded mag has less movement or shake than an empty magazine, but I do like the tighter fit of the MAC mag well better as I don't really care for anything on a gun that moves around or makes noise when you move or shake the gun.