HK Optics
I had to do a bit of digging to find the info for the optics. I found the instructions on HKPRO and copied them here for posterity.
G36C "shorty" rail:
G36 dual-optics w/ 3x scope below and red dot sight above:
G36E (export model) with 1.5x scope:
Improved 3x scope with picatinny rail:
SL8 rail converted to G36C profile:
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Instructions for Use
HK G36/SL8-1 Dual Sighting System
This document covers the installation, use and maintenance of the unique Dual
Sighting System on the Heckler & Koch 036 and SL8-1 rifles.
Sight Description
The Dual Sighting System, produced for HK by the Hensoldt Division of Zeiss
Corporation, combines an optical sight (either 1.5X or 3X magnification) and a
electronic red dot reflex sight together in one unit housed within a polymer
carrying handle. This unique sighting system was designed for and has been
fielded with the German military on their issue G36 rifles and carbines. This
sighting system can be fitted to the G36 and its variants or SL8-1 rifle without
modification using the hardware provided with the sight and the HK SL8-1
Multi-tool, or Phillips head screwdriver.
Once mounted the Dual Sighting System allows the user the means to zero each
sight independently and engage targets with either an optical sight or red dot
sight to account for various targets and shooting conditions. The intent of the
sight's design was for the shooter to use the optical sight for range estimation
and precise engagements of long- range targets (out to 800 meters) or for
engaging small targets, normally under lighted conditions.
The red dot sight is used more often for snap shooting, for engaging short range
or moving targets or for circumstances where the ability to keep both eyes open
during aiming is preferred. For this reason the red dot sight is often the
better choice for firing while moving or during periods of limited visibility or
darkness. Once zeroed the red dot acts as the aiming point for the shooter.
However, like all sighting systems the point of impact of the rounds on target
will vary depending on the distance at which the red dot sight was zeroed.
When using the Dual Sighting System on the SL8-1 it may be necessary to adjust
the cheek rest provided on the rifle for optimum head position. Generally
speaking the red dot sight is used with the head in a more upright position
wherein the head may not make full or firm contact with the butt stock. As head
position and cheek weld is less critical with a red dot reflex sight as long as
the red dot is visible to the shooter the target can be effectively engaged once
the sight is zeroed.
The two openings within the top of the carrying handle immediately forward of
the optical sight are for mounting the optional Hensoldt NSA80/II passive night
vision sight module.
Sight Installation
HECKLER & KOCH, INC
21480 PACIFIC BOULEVARD
STERLING, VIRGINIA 20166-8903 USA
WARNING
Clear the Rifle!
To install the Dual Sighting System on the G36 or SL8-1, first "clear" the rifle
by placing the safety/selector lever in the safe position, removing the magazine
from the rifle, locking the bolt rearward and inspecting the chamber for the
presence of a cartridge or empty case.
1. Once the rifle is "clear" use a Phillips head screwdriver or the HK
Multi-tool supplied with each SL8-1, to loosen and remove the three mounting
screws that hold the standard sight in place.
2. Pull the standard sight rearward off of the receiver of the rifle.
3. Slide the Dual Sighting System over the rear end of the receiver dovetail and
push it forward into place on the rifle. Insure that the front extension of the
carrying handle fits over the front mounting pedestal located on the rifle
forward of the cocking lever.
4. Once fully seated, reinstall the three locking screws to secure the sight to
the rifle.
NOTE
The longest of the three screws received with the Dual Sighting System (1 1/2
inches in length) goes in the front end of the carrying handle. The two shorter
screws (1 3/16 inches in length) are installed in the holes provided in the rear
of the carrying handle under the optical sight.
When inserting the screw place one unthreaded washer under the head of the each
screw. Insert the screws in the rifle from left to right. Install the threaded
nuts on the end of the screws visible from the right side of the carrying
handle. Hand tighten the screws using a Phillips head screwdriver or the HK
SL8-1 Multi-tool. If using a torque screwdriver to tighten the screws set the
torque setting to 250 NCM (22.5 inch pounds).
5. After mounting zero or reconfirm the zero of the sight(s) by following the
directions provided in the operators manual for the rifle. Unless the proper
torque setting is used when the sight is remounted there may be minor zero
changes after remounting.
Use of the Dual Sighting System
Optical Sight
The use and adjustment of the Optical Sight, to include the features and
function of the unique reticule pattern provided within the sight, is explained
in the operator’s manual for the rifle.
Electronic Red Dot Reflex Sight
The red dot within the upper sight of the dual sighting system is powered by
ambient light through a solar collector or by means of a battery contained
within the sight. During normal daylight conditions with the solar collector
shade on top of the dual sight open (slide forward) the solar collector will
illuminate the red dot as long as sufficient ambient light is available to do
so. The dot will glow brighter in stronger outdoor sunlight than it will indoors
or under artificial light. For periods when very little ambient light is
available or when the shooters prefers a brighter red dot, the battery back up
can be switched on.
Turning the Red Dot Sight On and Off
The on/off switch for the red dot sight is located on the right rear end of the
dual sighting system. Rotating this switch COUNTERCLOCKWISE will turn the sight
ON (when the white line aligns with the white dot), CLOCKWISE will shut the
sight OFF (when the white "0" aligns with the white dot - remember "0" means
"off').
The red dot cannot be adjusted for brightness or size nor are there intermediate
positions within the rotary on/off switch. The relatively large red dot is
designed primarily for quick instinctual aiming and not finite precision. For
precision engagements of small or distant targets the fine reticule within the
optical sight of the Dual Sighting System should be used.
If desired the shade of the solar collector can be closed to hide the glow of
the battery- illuminated collector during periods of darkness.
Changing the Red Dot Sight Battery
The Red Dot Sight uses only a single 3.6-volt size AA Lithium Battery. One
manufacturers model number for this battery is SL- 760. It is available at many
local stores, from Radio Shack or from HK directly under ID# 986444.
NOTE
Do not attempt to use other types of batteries in the red dot sight other than
that specified above or poor performance or damage to the sight may occur and is
not covered under warranty.
To remove the battery, locate the battery compartment positioned to the left of
the red dot sight opposite the on/off switch. Use a coin inserted within the
slotted cover to rotate the battery compartment 1/8th turn counterclockwise. The
battery compartment can then be pulled out only far enough to remove and install
the battery. DO NOT attempt to completely remove the battery compartment. The
correct orientation for the battery is noted within the battery compartment. To
close the battery compartment push in on and rotate the slotted cover 1/8th
clockwise until secure.
Dual Sighting System Maintenance
If the red dot fails to illuminate when the battery on/off switch is turned on
or the red dot flickers or is hard to see, try exchanging the battery with a
fresh one. If this fails to improve matters clean the battery contacts within
the battery compartment using a cotton swab and rubbing alcohol. If problems
persist, contact your unit armory, your HK dealer or Heckler & Koch.
DO NOT attempt to disassemble the Dual Sighting System for any reason. The solar
collector and red dot and optical sight lens should be cleaned with lens
cleaning tissues only to avoid scratching the lens.
DO NOT immerse the Dual Sighting System in cleaning solvent as damage to the
sights lens and rubber and electronic components may occur and is not covered
under warranty.
Zeroing
Due to the unique design of the Dual Sighting System both sights can be
independently zeroed for the same or different ranges. For instance a hunter
might prefer a long range zero (200 meters) for the optical sight for longer
shots and a 50 meter zero for closer shots on moving targets or when the
lighting conditions worsen.
The standard factory zero for rifles equipped with the Dual Sighting System is a
200 meter (219 yard) zero. Once established the 200 meter zero will insure that
the aiming points provided within the Optical Sight reticle will correspond to
the targets fired at longer distances when using 55 or 62 grain ammunition
(results may vary with different types and brands of ammunition). The Red Dot
Sight can also be adjusted using the same 200-meter zeroing procedure described
below.
Zeroing Procedure
The intersection of the Optical Sight crosshairs within the thick black aiming
circle, or the red dot of the reflex sight, should be used for zeroing.
1. With a target placed 25 meters (27.5 yards) from the firing position, adjust
the impact of the rounds on target until the center of a good 3-shot group
passes through the target 1 31. inches (45 mm) low of the point of aim. This
will provide a 200 meter zero without the need to fire on or have access to a
200-meter range.
2. Consult the applicable operators manual for the rifle being fired for the
method, direction of movement and degree of adjustment for the Optical Sight,
which are also the same for both sights within the Dual Sighting System.
3. Use the 2.5 mm Allen wrench contained within the HK SL8-1 Multi-tool to make
windage and elevation adjustments.