View Full Version : mac question

April 7, 2005, 07:45 PM
Does a M/10 M/11 or whichever one it is have to be registered for each caliber it will shoot? Can you just buy the conversion without having to change anything. I ask because I see some for sale that say "registered in 9mm and 45" while others just have one caliber listed........

April 7, 2005, 10:38 PM
If you plan on making the caliber change permanent then it must be registered for that. Otherwise it doesn't.

Like if you had a M10/45 only registered in .45, you could use the 9mm conversion upper and magwell adapter and everything is fine because the changes are not permanent.

But if you cut the old magwell out, weld a new 9mm grip onto the receiver, then put a 9mm upper on it, you would have to have a MAC that was registered for 9mm as well as .45. Because the changes are permanent.