Yes, they have serial numbers. These folks will date it: http://glockmeister.com/sernumb.shtml if it was made before 2000 Go to http://glocktalk.com/forums/showthread.php?t=412093 for a list
No specific characters. Glock serial numbers for a long time now have been 3 letters, then 3 numbers.
See link below to GLOCK 22
No, they are different calibers. A Glock 17 is 9mm and a Glock 23 is .40 S&W. A Glock 22 magazine would fit in a Glock 23.
Contact Glock and they will send you a manual for free. You can also download one from the Glock webiste.
The Glock 22 (full size .40 S&W) and the Glock 17 (full size 9mm Para) have the same external dimensions, and any holster will be interchangeable between the two.
You'll need to be more specific - there are 5 pistol models that use .40 S&W rounds. They are: -Glock 22 -Glock 23 -Glock 24 -Glock 27 -Glock 35
Police most often use the 9mm Glock 17 or the .40 S&W Glock 22. The glock 17 magazine holds 17 rounds (+1 in the chamber), while the Glock 22 holds 15(+1).
Serial numbers were not required before 1968
No, the Glock 22 barrel has an outside diameter that is larger than the hole in the front of the Glock 17 slide. your safest option is to buy a Glock 22 and a 9mm conversion barrel for the 22 slide. Then with the correct magazines you could use either 9mm or .40 S&W in a single frame and slide.
FBI and US Marshals issue Glock 22.
No. The 357 SIG magazine will not fit in a 40 caliber Glock such as the model 22.