Heckler And Koch HK Mark23 Operators Manual

11 CAUTION
A pair of Universal Mounting Grooves located
on the front of the Mark 23 frame allow for a
variety of accessories to be used with the
pistol. Improperly designed or installed
accessories may result in damage to the
Mark 23 mounting grooves and/or the Mark
23. Such damage is not covered under
warranty. Be certain to use only HK Authorized
Accessories and follow installation and
precautions carefully.
NOTE
Accessories designed for the Universal Self-
loading Pistol (USP) will not work on the...

12 safely by moving the decocking lever fully into
the decocking (down) position. The decocking
lever cannot be depressed (and therefore does
not allow the hammer to be lowered) if the
safety lever is engaged. The decocking lever
always springs back into its disengaged (up)
position due to the spring pressure exerted by
the decocking spring.
E. Safety Lever - The safety lever is an
ambidextrous “thumb” lever located on the rear
of the frame. It is actuated by the firing thumb of
the operator.  The safety...

13 F. Frame - The front and back straps of the
fiberglass reinforced polymer frame are
checkered to ensure a firm grip, even with wet
hands or under conditions of rapid fire. The
trigger guard is extended, recurved and grooved
to provide a firm grip when using two hands or
gloves. The bottom of the trigger guard is flared
on both sides in front of the magazine release
lever to shield the lever from accidental
actuation.
A threaded insert is molded into the front face of
the trigger guard and the frame is...

14
Figure 5  Firing
A.  Firing - (See Figure 5)  Pulling the trigger
rearward pulls the trigger bar forward. The
trigger bar pivots the sear actuator upwards
which disengages the firing pin block. At the
same moment, the sear is pivoted out of
engagement from the lower of the two shelves
located on the hammer. The compressed
hammer spring drives the hammer forward intothe rear end of the firing pin. The firing pin
strikes the primer of the chambered round. The
propellent is ignited by the primer and...

15
Figure 7  Ejection
E. Cocking - (See Figure 7) - As the slide
continues rearward the recoil impulse is
dampened by the buffer spring.  The recoil
spring is compressed and the hammer
recocked.
Figure 6  Unlocking
C. Extraction -The empty cartridge case is held
firmly against the face of the slide by the claw of
the extractor as the slide recoils rearward.
D. Ejection - (See Figure 7) -The rim of the
cartridge case strikes the stationary ejector. The
empty case is ejected from the open ejection
port....

16
Figure 8  Feeding
H. Locking - (See Figure 5) -The slide presses the
barrel forward.  As it does, the opposing angled
surfaces of the barrel locking block and recoil
spring guide rod pivot the rear end of the barrel
up into engagement with the ejection port in the
slide.  The slide is now fully forward and the
new round is ready to be fired. F. Feeding - (See Figure 8) -The compressed
recoil spring drives the slide forward.  If the
magazine is empty, the magazine follower will
lift the slide release...

17 2.5  Safety Features
A. Safety Lever - This safety blocks the release of the
cocked hammer in the SA mode. The safety lever
is an external, manually operated, ambidextrous
“thumb” lever located on the left and the right side
of the frame further most back from the trigger. The
safety lever must be manually actuated by the
operator. The shaft of the safety lever moves the
sear block into a position where it blocks the
movement of the sear actuator. The sear actuator,
in turn, does not allow the sear to...

18 D. Disconnector - This safety prevents the release
of the hammer unless the slide is fully forward
and/or the trigger is reset (released) between
rounds. This important safety prevents serious
malfunctions from occurring, such as “slam-
fires” (rounds that fire during loading), automatic
fire, or a round being fired out of the battery
(with the breech unlocked). The disconnector
disconnects the engagement of the trigger bar
and the sear actuator. The disconnector is
engaged (operating) after the slide...

19 4. Open Slide - lock slide open by pulling slide
rearward as you engage the slide release lever
(up). Watch for live round or empty case to be
ejected.
5. Inspect Chamber - inspect chamber for the
presence of a live round or empty case:
a. Visually view chamber through ejection
port.
b. Physically insert finger into chamber
through ejection port and check for
presence of cartridge case in chamber.
c. Remove any live rounds or empty cases
from the chamber or from within the
weapon.
The pistol is now...

20
Figure 9   Loading the Magazine
B. Unloading the Magazine - exert pressure with
the finger on the base of the cartridge case and
push each  round forward out of the magazine
one round at a time until the magazine is empty.
2.8  Loading Procedure
A. Administrative Loading - used to initially load
the pistol before it is to be fired.
Method A (Slide rearward, chamber empty)1. Make sure fingers are outside of trigger
guard and pistol is pointed in a  safe
direction at all times!
2. Insert magazine firmly...