SAR 18#6

ased on the assumption of the serial
numbers being sequential although this
may not strictly be true. A more accurate
description would be to say the changes
listed here occurred during a watershed
period during the middle of the
second generation. The change from
black internal parts to silver upgrade
parts, the locking piece relief cuts, and
the addition of a second line of text of
the lower cartouche are all relatively
contemporary changes roughly coinciding
with the change from the two-letter
to three-letter serial number range. Also
in this time frame, the spring and guide
rod assembly was upgraded to a one
piece unit.
A few years later, in 1994, Glock
began importing the model 24, which is
essentially the 2nd generation equivalent
of the 17L described earlier chambered
in .40 S&W. With the exception
of custom marked guns, all model 24’s
and all subsequent model numbers
have at least three letters in the serial
number range. Some time later the angle
of the right rear surface of the ejection
port was changed from a 90 degree
angle to something slightly larger. This
change occurred between the introduction
of the model 24 and the subcompact
models 26 and 27 in 9mm and .40
S&W respectively. What this means is
that one may encounter a model 24 with
the earlier 90 degree ejection port angle
but all models 26 and later had the
newer geometry.
The early model 26 and 27 pistols
were the first to incorporate finger
grooves in the front strap of the grip;
however, these were not checkered like
those that came before and after. It may
be easiest to regard the models 26-28
with the smooth front strap as generation
2 because they are like the proto
type for the generation 3 changes and
appeared prior to the addition of the accessory
rail that fully defines generation
3 guns. These first subcompact pistols
incorporated the “thumb rest” feature
at the top of the grip so they could be
legally imported into the U.S. market.
On the other hand, the large frame
subcompact pistols, models 29 and 30
(chambered in 10mm Auto and .45 ACP
Above: The “Short Frame” Glocks appeared in the 3rd Generation and were designated by an embossed “SF” in a cartouche on the
right side of the frame just ahead of the trigger guard. One model of the 21 SF even included an ambidextrous magazine release and
1913 rail attachment point in lieu of the traditional accessory mount. These features were added in anticipation of a U.S. Army handgun
contract that never materialized. Both features appear to have been discarded on all later models, although all future magazines
(regardless of caliber) retain the additional new magazine release geometry on the front wall of the magazine. These Ambidextrous
Glock 21 SF models represent a relatively limited number and short period of time for manufacture.
SAR Vol. 18, No. 6 56 Nov., Dec. 2014