The MK9 and CM9 should use the same mags.
http://www.kahr.com/kahr-mag-guide.asp
Anything larger will fit, too. I use the larger ones for the range and concealed carry spares.
Welcome to the forum and here's some more info:
Welcome to the Kahrtalk forum supported by Kahr Arms.
Here are a few essential links and things to do BEFORE you take your new pistol to the range, and ESPECIALLY BEFORE taking it apart and trying to re-assemble it! The Kahr is a different design… 6-7 unique patents cover the Kahrs. I’m not trying to imply that you don’t know anything about guns, but many don’t know anything about the Kahrs and some of the things you can do to damage or cause malfunctions of your new, or new-to-you Kahr pistol.
First, if you don’t have a manual, yet, or one didn’t come with your pistol, you can download the pdf file here:
http://www.kahr.com/PDF/kahrmanual.pdf
Impatient? Watch one of these videos FIRST! These videos can point out possible problem areas and emphasize correct procedures!
Take down and re-assembly videos:
T, TP, CW, P, & PM/CM Series:
http://www.youtube.com/watch?feature...&v=G2cZgVg_SwA
MK series:
http://www.youtube.com/watch?feature...mSCnIOaUk#t=0s
K series:
http://www.kahr.com/Pistols/Kahr-K9-Elite.asp
There are many links on fixing problems listed in several places… under the New Member or Kahr Tech sub-forums.
A very handy one is the Kahr Lube Diagram:
http://kahrtalk.com/showthread.php?t=14750
Many of your questions can be answered in these areas and you can learn how your Kahr works and not damage it with improper handling.
Frequently asked questions: http://www.kahr.com/faq.asp?
There are many helpful members here most of the time who might be able to help you, but as anywhere, there are many opinions and not all are correct. Be mindful of this before doing anything drastic to modify your pistol!
Wynn
USAF Retired '88, NRA Life Member. Wife USAF Retired '96
Avatar: Wynn re-enlists his wife Desiree, circa 1988 Loring AFB, ME. 42nd BMW, Heavy (SAC) B-52G's
Frédéric Bastiat’s essay, The Law: http://mises.org/books/thelaw.pdf
Thomas Jefferson said
“A government big enough to give you everything you want, is strong enough to take everything you have.”
and
"Peace is that brief glorious moment in history when everybody stands around reloading".