Originally Posted by Styrak
Within the same company, all Glock mags that are the same size or bigger should be compatible with any model.
So a KSC G19 can take KSC G19, G17, and 50 round mags.
I'd assume if the KJW is a TM clone it can take TM G17 mags, they'll just stick out a little.
Styrak is right, a KJW glock 23 will take TM as well as KSC G17 mags but they stick out a little less then an inch. I have a KJW G23 with both TM and KSC mags and they work fine