BY: NICK JACOBELLIS
The first Glock pistol I had the opportunity to inspect up close was a Generation 1 9mm Glock
17. This particular pistol was carried by a fellow U.S. Customs Agent, who survived the open ocean
night time ditching of a Black Hawk helicopter off the Florida Keys. After spending some 30 minutes
in the ocean, the crew except for the Pilot in Command (PIC), were rescued by the United States Navy.
Sadly, the PIC was unable to evacuate the sinking helicopter. His body was never recovered.
As soon as the survivors of this tragic incident returned to the (Miami) Customs Air Unit at
Homestead Air Force Base, one of our firearms instructors disassembled their issued and personally
owned firearms and had each weapon thoroughly cleaned and lubricated. This was done to prevent
corrosion after these firearms were being completely submerged in salt water. When I had the
opportunity to inspect the early model Glock 17, it looked as good as the day it was made, proving that
the Tenifer Finish was incredibly corrosive resistant. Another special agent that I worked with was less
fortunate, when he fell into the ocean during a vessel boarding operation. Even though this agent’s
handgun, that was manufactured with a blued steel finish, was thoroughly cleaned with fresh water and
properly lubricated, this particular firearm had to be sent off to receive an after market corrosive
resistant finish, in order to remain in service.
In 1982 the Generation 1 9mm Glock 17 was officially adopted for use by the Austrian Armed
Forces and Police. This history making event occurred, when this polymer framed pistol successfully
competed against some of the most famous 9mm firearms in production at that time. Once the 9mm
Glock 17 was officially adopted by Austrian government and a description of the testing protocols were
publicized, other military and law enforcement organizations around the world started evaluating and
adopting the Generation 1 9mm Glock 17.
The Gen 2 Glock 17 was introduced in 1988. Gen 1 and 2 Glocks are easily distinguishable
from the Generation 3, 4 and 5 models, because the grip portion of the frame on the first two
generations lack finger grooves. The Gen 1 Glocks also featured a pebble finish to the grip portion of
the polymer frame. In contrast, the Gen 2 Glocks featured checkering and serrations on the grip portion
of the polymer frame. These features increased the gripping surface on the Gen 2 pistols, which in turn
improved ergonomics to some extent.
The popularity of the Generation 1 and 2 Glock 17 motivated Glock end users to look forward
to the development of other Glock pistols. The creation of the 9mm Glock 19 and the 9mm Glock 26
provided armed professionals with a compact and subcompact size polymer frame pistols, that were
easier to conceal than the full size Glock 17. Different size pistols chambered in various calibers, to
include .40 and .45, were also added to the Glock lineup.
In 1998 the Generation 3 Glock pistols featured an accessory rail, that was designed for use
with a tactical pistol light or a laser. Other improvements made to the Gen 3 Glocks included finger
groves on the front of the grip portion of the polymer frame and thumb rests on the upper sides of the
grip. As the Generation 3 Glocks evolved, an improved locking block and a “locking block pin” was
added, along with a redesigned extractor, that also served as a loaded chamber indicator. The locking
block pin can be seen positioned on the top of the frame, above the pin that holds the trigger in place.
Gen 3 pistols were also available with the traditional black colored polymer frame, as well as in flat
dark earth and olive drab.
The Generation 3 series of pistols also included the sub compact Glock 36 chambered in .45
ACP, as well as the sub compact Glock 42 chambered in .380 ACP caliber. Both the Glock 36 and the
Glock 42 made “firearms history” because they were the first Glock pistols to operate with a single
column magazine. The Glock 42 was followed by the Glock 43, which is a sub compact 9mm variant,
that also operates with a standard 6 round magazine. Both the Glock 42 and the Glock 43 are ideally
suited for “super” concealed carry applications.
It should also be noted, that during the production of Gen 3 Glocks the company transitioned
away from applying a Tenifer Finish on their pistols. This was done due as a result of environmental
The RTF2 or Rough Textured Frame 2 models were also developed toward the end of the
Generation 3 series of Glocks. The first RTF2 was a Glock 22 chambered in .40 caliber. The RTF2
pistols featured scalloped slide serrations positioned at the rear of the frame and a different style of
checkering on the polymer grip.
As their models evolved in 2009, Glock fitted their Generation 4 pistols with a double strand
captive recoil spring, as opposed to the single coil captive spring that was used in the earlier generation
of pistols. Doing so, tamed felt recoil a bit, especially in the larger/heavier calibers. I personally found
this to be true while field testing various Gen 4 Glock pistols. The Gen 4 pistols were also designed to
be used with a set of different size interchangeable backstraps. These interchangeable backstraps are
made of polymer and are held in position by a polymer pin. This feature improves ergonomics by
enabling a Gen 4 Glock to be comfortably operated by installing a backstrap, that better suits the hand
size of the operator.
The current Generation 5 Glock pistols date back to 2017 and include a number of new models,
as well as modifications and or enhancements to the design of these amazing firearms. One of these
changes involves the use of a DLC or Diamond Like Carbon Finish. While the Tenifer coated Glocks
definitely have their fan base, Glock pistols, regardless of their generation, hold up to the harshest
operating conditions imaginable. This is evident by the rather massive number of Glock pistols that are
in service with armed professionals throughout the world. There is even a large number of hunters and
other legally armed individuals who carry one of the heavier caliber of Glock pistols, when they
operate in remote wilderness areas. These individuals do so, to have immediate access to a flawlessly
reliable and hard hitting pistol, that can be used in an emergency to effectively engage an aggressive
The Gen 5 Glocks are also fitted with a captive dual recoil spring. As stated above, I can
personally attest to benefit of using a captive dual recoil spring assembly to tame recoil. In fact, four
of the softest shooting Gen 5 Glock pistols in my arthritic hands are the 9mm Glock 34, the 9mm Glock
19X, the 9mm Glock 43X and the 9mm Glock 48.
The Gen 5 43X and the Glock 48 also made “Glock history” because they are ideally suited for
concealed carry applications. Both the 43X and the Glock 48 are similar in design to the 9mm Glock
43, in that these Gen 5 pistols also operate using a single column magazine. As a point of information,
the 43X is considered a sub compact pistol, while the Glock 48 is considered a compact model. The
difference between the 43X and the 48 is the length of the slide/barrel, with the Glock 43X utilizing a
3.4 inch barrel and the Glock 48 using a 4.17 inch barrel. (The length of the barrel on a Glock 19 is
4.02 inches.) In essence, the Glock 48 is “basically” a Glock 19 size pistol with a slimmer grip that
accommodates a single column 10 round magazine, as opposed to the 15 rounds in a staggered
column Glock 19 magazine. Both the Glock 43X and the Glock 48 use the same 10 round single
The Gen 5 Glocks also include Modular Optic System (MOS) variants, that can serve as a
Personal Defense Weapon, Compact Personal Defense Weapon and a Sub Compact Personal Defense,
by installing a compact optic to the rear of the slide. Depending how your pistol is configured, a
compact optic provides the end user with a “single” sighting system in the form of an illuminated
colored dot. MOS Glocks can also be equipped with a set of higher profile/elevated “suppressor”
According to one veteran law enforcement firearms instructor that I know, a number of police
officers in his department have dramatically improved their level of proficiency, while qualifying with
their 9mm Glock service pistols, after having their pistols fitted with some type of illuminated optic.
If using this type of sighting system dramatically improves your level of proficiency, then you should
strongly consider adopting this type of sighting system. Another alternative is to continue training
under the tutelage of a highly respected instructor, until you are able to improve your hit potential,
while using a traditional set of standard iron sights and or night sights.
FRONT LINE SERVICE
During the Global War on Terrorism, Glock pistols in various calibers served with a number of
U.S., NATO/Coalition military entities. One interesting tidbit of information, that was relayed to me by
an unnamed source, described how Glock 21s with six magazines and night sights were utilized by one
particular U.S. Army unit serving in Afghanistan. When one of these .45 ACP caliber Glock pistols
ended up on an unpaved road in a hostile location, when it was inadvisable to stop, several heavily
laden vehicles were forced to drive over the dropped pistol. When this convoy later returned to the
same area and it was safe to stop, the dropped pistol was recovered. The only damage to this particular
Glock 21 involved damage to the rear sight. Once the damaged sight was replaced, this pistol was
reportedly put back in service.
MORE IS BETTER
The Department of Defense recently awarded Glock a $15 million dollar 5 year contract, to
provide 1500 9mm Glock 17s, 5000 9mm Glock 19s and 2200 9mm Glock 26s, to include Generation
3, 4 and 5 pistols, as well as Gen 4 and 5 MOS Glock 19s to authorized military units. In addition, this
contract authorizes the purchase of factory night sights, standard sights, spare magazines, spare parts,
as well as metric and standard threaded barrels for use with suppressors.
What’s interesting about this contract is the diverse nature of the Glock products that are
authorized for purchase by designated DOD entities. While one would expect certain elite DOD units
to use pistols equipped with an illuminated optic and or a suppressor, one of the most interesting
aspects of this contract is the acquisition of 2200 9mm Glock 26 sub compact pistols. I say this,
because the last time the U.S. Armed Forces utilized a large number of more concealable compact
handguns, was when combat aircrew personnel and military special agents carried short barreled Smith
& Wesson and Colt revolvers chambered in .38 Special caliber. Prior to the use of short barreled .38
Special revolvers, the Colt Model 1903 and or the Colt Model 1908 Pocket Auto, also known as the
Pocket Hammerless, were the most compact sidearms issued to designated U.S. military personnel.
The Colt Pocket Autos that were issued during World War II were chambered in .32 and .380 ACP
calibers and had a corrosive resistant Parkerized Finish.
Being able to carry a sub compact pistol, that is chambered in the same caliber as larger Glocks,
that can also reliably operate while using the same magazines as larger Glock pistols, has been a
hallmark capability of Glock pistols, ever since the sub compact Glocks became available. This
capability was originally taken advantage of by law enforcement officers, who carried a full size 9mm
Glock 17/34, or a compact 9mm Glock 19 as a primary service pistol, with a 9mm Glock 26 as a
The fact that the Glock 26 can be easily carried in an inside the pant’s holster, or in an ankle
holster, makes this pistol ideally suited for “super” concealed carry applications. Even though the
Glock 26 is a Sub Compact Personal Defense Weapon, a Glock 26 can also be relied on to serve as a
primary sidearm. As a result of the current $15 million dollar contract, designated DOD personnel will
now be able to have tremendous versatility, when it comes to selecting the right Glock handgun for
To date, I have either test fired/evaluated and or owned various Glock pistol in every available
caliber except .22 LR. Each and every one of these Glock pistols proved to be flawlessly reliable.
My personal favorites are the Gen 2, 3 and 4 9mm Glock 17, the Gen 3 Glock 21SF .45, the
Gen 3 and Gen 4 Glock 21 .45 , the Gen 4 Glock 22 .40 cal, the Gen 5 9mm Glock 19X, the Gen 5
9mm Glock 43X and the Gen 5 9mm Glock 48.
*Author’s note: I recently purchased a surplus law enforcement Generation 2 9mm Glock 17
and a surplus Generation 4 Glock 22 .40 caliber pistol from Century International Arms. While the
Gen 4 Glock 22 was in Excellent Condition and didn’t look as if it was ever fired, the Generation 2
9mm Glock 17 displayed some external wear and tear, but upon inspection of its internal components,
didn’t appear to have been fired all that much. The holster wear on the slide of the surplus Gen 2 Glock
is a purely cosmetic issue, that will not detract from the ability of the Tenifer Finish to protect this
pistol from corrosion. This fact alone is a tribute to the ruggedness of the early generation of Glock
pistols. The surplus Glocks that I recently purchased were upgraded and made more serviceable as a
Personal Defense Weapon, by installing Glock night sights and Talon Rubber Grips.
If you are ever in the market for a surplus pistol, I recommend periodically checking the on line
list of handguns that are posted for sale on the Century International Arms Website. Sometimes you
can get very lucky and can locate a pistol or a revolver in very good to excellent condition that is priced
right. I have also found Century International Arms to have excellent customer service.
Nick Jacobellis is a Medically Retired U.S. Customs Agent and a former NY police officer who was physically disabled in the line of duty while working undercover as a federal agent. To date, the author has published over 205 magazine articles and nine action-packed nonfiction, historical fiction, and fiction books: Controlled Delivery Books One and Two, The Frontline Fugitives Books I, II, III, and IV, Buck Banderas U.S. Marshal Books One and Two and A Special Kind of Hero. These books have received 5 Star reviews and are available on Amazon.com (US), and (UK). He was born and raised in Flatbush section of Brooklyn NY and has an BS Degree in Police Science from John Jay College of Criminal Justice.