2nd Variation: The caliber mark was changed to .40 SW and was marked on the slide and top of the chamber. The lowest serial number I have observed is a G23 SL prefix, the marking ended between the CAM and CER range.
USMCR 1997 - 2004
PAARNG 2011 - Present
Founder - Glock Collectors Club PA Glocker #39
Looking for G22 PE389US
Multiple Armorer Certifications