Home Projects G36k Rhox505’s G36KE Conversion

Rhox505’s G36KE Conversion

by Arnie

G36KE Conversion



the picture above is very out of date. it was taken prior to
the new outer barrel, flash hider straightening, and carry handle

since I first got into Airsoft, I’ve been dreaming about
a G36K. I was very excited to hear about the production of the
G36C, albeit a little disheartened that they had chosen to produce
the less-popular C version first. After my friend got a G36C,
the quality of construction and practicality put my AEG’s
which I had poured thousands of dollars into, to shame. I had
to have one of these guns. But there was no point in buying
the C and then buying the K right after it. But after hearing
that it would be at least another year before the K was produced
by TM, I decided that I could not wait – I had to take
the project into my own hands. One advantage to doing it yourself
and using real steel parts, is that…well, half your gun
is made using real steel parts! If you ask me, that is very
cool — and even better than having the official Marui version
(I’m sure their optical sight won’t be as good anyway).

a real G36KE for comparison

I wasn’t sure what kind of battery
storage capacity a real G36K forearm had, but I assumed it would
at least hold the 9.6v 1500maH custom battery made for the G36C.
Experience has taught me that ROF is actually more important
than FPS, so I proceeded with my base upgrades with that in
mind. I wanted it to be either really silent, or really loud.
It was a tough choice, but I eventually decided that a silencer
would be cumbersome and less practical, so I should just go
with loud internal upgrades. This meant a Type-0 cylinder (also
better considering I was going to increase the inner barrel
length), and an aluminum piston head. I decided to test out
new SP100 spring, which is supposedly more battery efficient
and reliable.

are a couple people who had already converted their G36C’s
before me. There pages can be viewed here:

parts which are different on the G36K are the carry handle,
forearm, butt stock, flash hider, outer barrel, and gas tube.
None of these are particularly easy parts to acquire.

I decided to pass up on the red dot scope which
is often pictured mounted above the optical scope. These red
dot units have a reputation for not being very good, cannot
be purchased separately, and have a price tag along with the
carry handle of over $600. I actually prefer the look of just
the optical sight anyway, and I found a great deal on a 3x one
for $250 used (they usually go for $350, and also can be made
in 1.5x but those are less common). According to HK nomenclature,
this is technically this a G36KE, because the G36K includes
the red dot sight.

was happy to find that my sight did not have any black flecks
in the lens, which is apparently a commonly known problem among
these things. It is difficult for me to get the reticule (a
cross with a small circle in the center) to appear crisply,
but it is still very easy to aim with. The 3x magnification
is just right for Airsoft; I can see where my BB hits without
the deceiving curving arc that you will see with higher magnification
scopes. It is also very easy to adjust this scope to be on target.

the carry handle was the most difficult modification that I
had to do. It can actually be made to fit on without any modification
(as seen in the digital camera pics), but it is a VERY tight
fit, and it is not possible to get the front hole to line up
properly without modification. First, I shaved/sanded down the
rail which it slides on a little bit. I also cut off the slight
ridges on the fore ward part of the middle screw-stub on the
G36C. The most important part of this modification is the shorten
the middle stub by slicing off a couple millimeters from the
back end. This allows the carry handle to slide all the way
forward (instead of stopping a few millimeters short). Then,
the middle and front holes need to be re-drilled. This is a
minor correction because the holes do not line up perfectly.
The screws from the G36C will work, except for the front screw,
which is not long enough, and must be replaced at a hardware

without modifications, the carry handle can still go on
but it does not go all the way forward.
front and middle screw holes must also be bored out

carry handle attached after mods

view through 3x optical scope

Extension and Flash Hider:
I bought an aluminum outer
barrel section that screws onto the G36C’s existing threaded
outer barrel from Ko. For the flash hider, I purchased an Airsoft
HK53 flash hider (real G36K flash hiders are not easy to find
and can go for as much as $150, from what I hear.) The HK53
flash hider is a pretty good replica, but not perfect. The prongs
are about 6mm shorter than the real ones, and there is also
no inset on the threads like on the real one. This causes it
to be the correct overall length, but expose more outer barrel,
than the real one.

working with Ko and sending him the specifications of my HK53
flash hider, he was able to custom make me a new prototype barrel
extension that more accurately reflected the real-steel specifications.
In this prototype, he was able to reduce the diameter a little
bit to be the correct size, and compensate in length for the
miniscule (1mm width) inset of the threading on the HK53 flash
hider. This new barrel looks much more real.

I lightly applied some threadlock to keep the flash hider from
rotating out of position.

old barrel extension

new barrel extension

A number of people were selling resin molds of the
forearm, but I didn’t particularly want a resin mold,
and I also didn’t want the holes for the side rails. After
looking around at various online HK retailers for the parts
I needed, I was able to find very few of them in stock. It turns
out HK has suspended their shipments to the US (as I understand
it), and as a result all the parts have been bought up by SL8
owners. To my luck, Ko also had an extra one of these for sale.

forearm requires some modification to fit, because it is not
as deep as Marui’s. This cut is not entirely trivial,
and I thought it best to disassemble the gun first.

the section above the stub must be removed so that the
forearm can slide on

To my dismay, my 9.6v 1500mah custom battery, which
fits ‘easily’ (relative to fitting MP5A5 batteries)
into the G36C forearm, would not fit into the new forearm! After
a few minutes of panicked fiddling, I did finally manage to
get it to fit. It is difficult because the real forearm is not
only not as deep as the Marui one, but also slimmer. However,
when I did finally come up with a way to get it to fit, it does
not put pressure on the sides which is good. Also, it is possible
to add up to 4 more cells to the front of this battery, meaning
that a 12v 1500mah will fit. So I will probably do that someday,
and upgrade the spring accordingly to a SP130.

battery is viewable through the holes in the top half of the
forearm, as well as the bottom holes. The plastic strip which
is inside the G36C forearm would be long enough to cover the
bottom holes in the G36K forearm, but I’m not quire sure
how to remove it without breaking it yet. I plan on doing this
someday, though.

This is the most difficult part to find. I was
actually able to find a couple, but after a lot of careful consideration
I decided to pass up the butt stock for a few reasons:

the G36C butt stock was reputedly more comfortable, and offered
better eye-relief. Many G36K/SL8 owner’s swap their
stock with the C for this reason.
2) the G36K stock is either a different shade or has a different
level of shininess. At any rate, I didn’t like how it
could be distinguished in photos.
3) The hinge hole does not line up exactly with the real thing,
so it would have to be re-drilled, and this leaves room for
error, which could result in destroying the stock or causing
it to be less sturdy than Marui’s stock
4) If you can find one of these for sale, they usually go
for about $250 used…

Of course, the inner barrel needed to be extended
to match the outer barrel and take advantage of the full accuracy
potential that was now available. Most people are saying that
the M4A1 barrel is the correct one for this mod, but unless
your G36K is unrealistically long, this will be too long. Unfortunately
there are a lot of different numbers going around for the length
of the barrel of the M4A1. Well, it is actually 363mm, which
is about 1cm too long.

M4A1 TN barrel has 2 circumventing notches at about 1cm intervals
from the end. Conveniently, I found that the first interval
gives the perfect length. Cutting it was the easy part –
then I needed to use some Dremel tools to crown the end so that
there would be no burs to interfere with accuracy. After all,
it would be pretty hypocritical to buy a longer tight-bore barrel
and then reduce the accuracy to less than you started with by
leaving burs.

As you can probably tell by now, this gun was not cheap.
Here’s what I bought and what it cost me:

1 X TM G36C (mod)
$12 1 X Guarder SP100 Spring For AEG
$43 1 X Sanyo 9.6v 1500mah battery for G36C
$70.50 3 X TM G36C standard magazine
$13 1 X Systema Aluminum Piston Head with Bearing
$10 1 X Systema N-B Cylinder Type-0
$65 Express shipping fee to USA
TOTAL $432.50

1x HK G36K Forearm
$35 1x Custom G36K Outer Barrel Extension Painted
$4.30 Express Shipping Fee
TOTAL $100

1x KM TN M4A1 6.04mm Inner Barrel (mod)
$55 1x Guarder HK53 Flash Hider
$0 Shipping Fee
TOTAL $105

HK G36KE Carry Handle with 3x Optical Sight
$0 Shipping Fee
TOTAL $250

PRICE = $887.50


conversion: http://kope.com/airsoft/G36K.html
Wallace’s conversion: http://pageproducer.arczip.com/daedalus03/g36k.html

G36c review

on this review in the forums

Monday, May 5, 2003 7:15 PM
Copyright 2003 ArniesAirsoft

Cookies are used improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More