I'll tell you what my trainer told me at my last Glock Cert'd Armorers class. When the Fed AWB went into affect Glock moved the caliber designation up towards the feed lips to make room for the "Restricted, LE Only" marking. If you look at your mags you'll see the BOTTOM of the "9mm" caliber designation letters is in line with the magazine stop protrusion on the left side of the mag. The pre-ban mags cailber designation had the TOP of the "9mm" almost in line with the mag stop protrusion. According to my instructor when the AWB expired, Glock removed the "Restricted, LE Only" wording but left the caliber designation in the upper position to save having to build new mag molds. So according to my instructor, if your caliber designation numbers/letters sits above the mag stop protrusion then they are post ban, if it sits below the mag stop protrusion then its pre-ban.
I confirm what LenS said about Glock not dating their mags etc but just giving you what was taught to me and is being taught to civs/LEOs at all Glock Armorer classes.
That's wonderful- so they're telling armorers stuff that's not based on anything the company has officially stated?
![Laugh [laugh] [laugh]](/xen/styles/default/xenforo/smilies.vb/012.gif)
Either that or some of these trainers are just parroting things they read in various books about Glocks.
-Mike