The finger grooves, the thumb rests, and the rail for tac lights etc.

Originally Posted by Dynamik1

Hey Team-
What's the difference between 2nd Gen and 3rd Gen frame-styles?
If there is a previous thread that discusses, feel free to just point me to it, but I didnt see one.

- 1st Generation has the smooth, rounded “pebble-grip”.
- 2nd Generation has the “Grenade-style” checkering with NO fingergrooves (see picture).
- 3rd Generation has BOTH fingergrooves AND accessory rail on the front dustcover.
- If you have a subcompact (G-26, -27, -28, -29, -30, -33, -36) OR a “transition model” when Glock was putting fingergrooves but no accessory rail, then you have a 2.5 Generation. There is even a slight variation here, as some of the earliest G-26 & G-27s had smooth fingergrooves, without checkering in-between the grooves. Some people do not count the sub-compacts as 2.5 Gen since they came out after the 3rd Gen frames were already being made. Note: newer -29, -30 are now coming with rails.

This is what I always look at for reference. This is also where the quote was pulled from (it has pictures as well ):

http://www.glocktalk.com/forums/showthread.php?t=412093 (<----ETA: Todd, I just saw your post about links to other forums. Please delete this link if necessary, I was just providing the source for the quote. )

-Jeff-

Thanks Jeff!! Much appreciated!

http://www.glockfaq.com/default.htm

The post is about frame styles but there is an important difference between the 2nd and 3rd generation G22 and G23. In the third generation Glock changed the barrel design somewhat at the chamber end. There is more support in the chamber in the third gen guns. Unless you need the rifling for lead or a match barrel, there is no necessity for buying an after market barrel for the third gen. A gunsmith buddy of mine brought this to my attention and demonstrated the difference in the shop. I have seen no reference to this in Glock literature but you can really see the difference with a cartridge inserted into a second and third gen barrel out of the gun. I think maybe Glock was trying to downplay a need for modification (the Kaboom syndrome publicity) I shoot nothing but premium jacketed ammo in mine anyway but it is comforting to know it has the modification..