Clints M4 Carbine Prop

BOM and assembly instructions

Version 1
8 July 2017


CLINTS M4 CARBINE PROP !1

Clints M4 Carbine Prop 1
BOM and assembly instructions 1
M4 Carbine Prop 4
History of the M4 Carbine 4
Foreword 5
Required Tools 6
Printer Calibration 9
First Layers 9
Temperature and cooling 9
Bill of materials 10
Printed parts: 10
Hardware 27
Before assembly 29
Charging handle assembly 35
Receiver assembly 37
Stock Assembly 45
Attaching the Stock to the Receiver 50
Barrel Assembly 51
Rear sight/Handle Assembly 54
Insert The Magazine and test everything 58

CLINTS M4 CARBINE PROP !2

CLINTS M4 CARBINE PROP !3
 M4 Carbine Prop
History of the M4 Carbine

The M4 carbine is a shorter and lighter variant of the M16A2 assault rifle. The
M4 is a 5.56×45mm NATO, air-cooled, direct impingement gas-operated,
magazine-fed carbine. It has a 14.5 in (370 mm) barrel and a telescoping stock.
The M4 carbine is extensively used by the United States Armed Forces and is
largely replacing the M16 rifle in United States Army and United States Marine
Corps combat units as the primary infantry weapon.[5][6]
The M4 is also capable of mounting the M203 and M320 grenade launchers.
The distinctive step in its barrel is for mounting the M203 with the standard
hardware. The M4 is capable of firing in semi-automatic and three-round burst
modes (like the M16A2 and M16A4), while the M4A1 is capable of firing in
semi-auto and full automatic modes (like the M16A1 and M16A3).

As with many carbines, the M4 is handy and more convenient to carry than a
full-length rifle. The price is slightly inferior ballistic performance compared to
the full-size M16, with its 5.5" (14 cm) longer barrel. This becomes most
apparent at ranges of 200 yards and beyond.
While the M4's manoeuvrability makes it a candidate for non-infantry troops
(vehicle crews, clerks and staff officers), it also makes it ideal for close quarters
battle (CQB). The M4, along with the M16A4, have mostly replaced the
M16A2 in the Army and Marines.

CLINTS M4 CARBINE PROP !4

 Foreword
This model has been optimised for 3D Printing on a FDM printer. where ever possible the use
of supports has been minimised to ensure the best aesthetic qualities but as with any complex
geometry it is some times not possible and supports must be used.

However with the correct tuning of your support settings you should be able to achieve good
supports which break away cleanly leaving little if any post printing tidy up work to be done.

I have designed this model to print on a Prusa i3 mk2 (print area 250/210/210mm XYZ) as
this is what I own however only a few of the large parts require the larger print bed of the
mk2 many of the small parts I will print on my PrintrBot Simple metal (150/150/150 XYZ).

A future update of this model may see the larger parts split to make printing on smaller
machines possible so if you would like to see this done, let me know.

My Slicer of choice is Simplify3D S3D. Throughout this document I will be referring to print
settings as they appear in S3D, but theses settings can usually be found in most Slicer software
although perhaps as a different name. One advantage of S3D is its ability to create and edit
custom supports, I will be taking advantage of this heavily for components that require
supports. Again though you may be able to achieve similar results in other Slicer software
through that apps support settings.

CLINTS M4 CARBINE PROP !5

 Required Tools

Side cutters - Useful for trimming and cutting

Needle nose pliers - Good for removing support

material

Craft knife - For cleaning up of printed parts

Small craft mallet - For gently fitting parts together

CLINTS M4 CARBINE PROP !6

 2-4 sets of clamps - Alternatively some strong rubber
bands. This is to keep the parts firmly pressed
together while glueing

Assorted drill bits - Uniforming and/or reaming

holes in the printed parts, use of a drill is not
necessary twisting the bits by hand with your fingers
will be all that is needed and will give good clean
results

Rotary tool and assorted sanding bits - some prints

may have to have to be sanded to fit together
depending on the accuracy of your printer.
Alternatively you could just use sand paper.
!

3mm hex key

Jewelers files - Optional but good for precise

trimming/cleaning up of printed parts

CLINTS M4 CARBINE PROP !7

 Super glue - for permanent assembly of printed
parts

CLINTS M4 CARBINE PROP !8

 Printer Calibration
For best results a well calibrated printer is a must, this will ensure parts fit together well and
look good.

A printer calibrated to within +/-0.1 mm is easily achievable most quality printers will come
out of the box doing this. If not though you should work on calibrating your printer using the
many guides available many specific to brands and models.

First Layers
Calibration of your first layer using your printers or slicers Z offset setting is key
to getting prints that adhere to the bed well and for this model can be assembled
and glued together easily.

your first layer when removed from the print bed should be smooth and
“glassy”.

Temperature and cooling

Finding the correct temperature for your filament will produce quality printed parts. The M4
Carbine prop prints with a lot of unsupported bridges and over hangs.

Printing the #3dBenchy model until you achieve quality results is a good way to tune your
printer and not waste too much filament. Good results depend highly on the extrusion
temperature and cooling.. When printing over hangs and bridges a suitable extrusion
temperature and effective cooling will reduce and even eliminate sagging which gives
undesirable print results.

Trial and error is needed here but starting at the recommended temperatures and then going
up or down in small increments is the key to success.


CLINTS M4 CARBINE PROP !9

 Bill of materials
Printed parts:
The following images show the orientation of all the printed parts and the location of support
material if needed is displayed in green. Simplify3D will allow you to generate these supports
and then remove any un-needed support material or add additional supports

CLINTS M4 CARBINE PROP !10

!

CLINTS M4 CARBINE PROP !11

!

CLINTS M4 CARBINE PROP !12

!

CLINTS M4 CARBINE PROP !13

!

CLINTS M4 CARBINE PROP !14

!

CLINTS M4 CARBINE PROP !15

!

CLINTS M4 CARBINE PROP !16

!

CLINTS M4 CARBINE PROP !17

!

CLINTS M4 CARBINE PROP !18

!

CLINTS M4 CARBINE PROP !19

!

CLINTS M4 CARBINE PROP !20

!

CLINTS M4 CARBINE PROP !21

!

CLINTS M4 CARBINE PROP !22

!

CLINTS M4 CARBINE PROP !23

!

CLINTS M4 CARBINE PROP !24

!

CLINTS M4 CARBINE PROP !25

!

CLINTS M4 CARBINE PROP !26

 Hardware

Qty. 1 H1
!

Qty. 1 H2
!
5x12mm

H3
compression spring

! Qty. 1
7x33mm

H4
compassion spring

Qty. 1
5x25mm

H5
compassion spring

Qty. 1

CLINTS M4 CARBINE PROP !27

 85x18mm
compression spring

Qty. 1 H6
I purchased an assorted packet of springs from the local hardware store https://
www.bunnings.com.au/spring-assortment-century-no1_p3969419



CLINTS M4 CARBINE PROP !28

 Before assembly
Before assembly it is important to do some post printing work on the parts to
ensure they fit well together due to the very tight tolerances to ensure a nice
snug fit, not to tight and not to lose.

All holes should be uniformed and there corresponding parts fitted and tested.
This can be done my using a drill bit and twisting it by hand through the holes
or with jewellers files.

The edges that were in contact with the print bed may need to be sanded or
filed to take any elephant footing from the first layer off of them.

All threaded parts will need to be mated with there corresponding part gently
start the two threaded parts to gather ensuring they are not cross threaded, then
gently twist the threads together just a fraction and then back it off, repeat this
twisting on then backing off until the parts are entirely threaded together. Then
they may still need to be screwed and unscrewed multiple times to lap and mate
the parts. Using some water based lubrication can also help this process. Do not
allow the parts to become hot from the friction as this will melt the threads.

CLINTS M4 CARBINE PROP !29

CLINTS M4 CARBINE PROP !30
CLINTS M4 CARBINE PROP !31
CLINTS M4 CARBINE PROP !32
CLINTS M4 CARBINE PROP !33
CLINTS M4 CARBINE PROP !34
 Charging handle assembly

1. Take the spring catch and share handle and use screw H1 to attach the spring catch to the
charging handle

2. Insert the spring into the cut out for the charging handle latch

3. Insert the charging hand latch into the slot pushing down the spring

CLINTS M4 CARBINE PROP !35

4. insert the pin (5mm length of 1.75mm filament)


CLINTS M4 CARBINE PROP !36

 Receiver assembly
1. Take one half of the Receiver and insert 23 Pins cut from 1.75mm filament into all the
pin holes.

2. Place the Charging handle and main spring H6 into the cutout as shown in the picture.

CLINTS M4 CARBINE PROP !37

3. Place the Trigger and trigger spring into the slots in the receiver

4. Place the top half of the receiver down over the lower half making sure the pins line up
with their holes and that the charge handle, trigger and springs all stay in place. This can
be difficult. You can also use some super glue for a permanent assembly but it is not
necessary


CLINTS M4 CARBINE PROP !38

5. Insert the selector lever into its hole

6. insert the selector lever detent and spring into their hole on the other side.

CLINTS M4 CARBINE PROP !39

7. Place the grip onto the receiver this will hold the Detent and detent spring in place and
then insert the Grip screw to hold the grip in place.

CLINTS M4 CARBINE PROP !40

8. Insert the forward assist plunger spring into the hole making sure it sits in the hole fore the
spring inside the main hole.

9. Insert the forward assist plunger taking note of the cut out on the plunger this must line
up with the hole for the assembly pin.

CLINTS M4 CARBINE PROP !41

10. Push the forward assist plunger all the way in then insert the assembly pin. You can then
let go of the Plunger as it will be handle in place by the pin

CLINTS M4 CARBINE PROP !42

11. insert the mag catch sting into its hole

12. insert the mag catch button into the hole over the spring and push it all the way into the
receiver until it stops

CLINTS M4 CARBINE PROP !43

13. Insert the Mag Catch into the hole on the opposite side while holding the mag button
pressed all the way in screw the Mag catch as far into the button as you can and then line
it up with the cut out slot for the catch and let go of the mag button

CLINTS M4 CARBINE PROP !44

 Stock Assembly
1. Take the stock pin and cap and screw them together. You can use some super glue to
make it a permanent assembly.


CLINTS M4 CARBINE PROP !45

2. take the stock and drop the spring through the hole in the top down into the hole below


CLINTS M4 CARBINE PROP !46

3. slide the Stock Latch over the pin, while holding the pin depressed with your finger or a
tool.

4. While holding the pin depressed screw the thumb nut onto the pin to hold everything in
place. Only screw the thumb nut dow until it is level with the thread so that the pin sticks
out inside the stock.

CLINTS M4 CARBINE PROP !47

5. using the stock latch to operate the pin pull down on the latch to allow the buffer tube to
enter the slide. You can now squeeze the stock latch to operate the pin and make stock
adjustments


CLINTS M4 CARBINE PROP !48

6. Optionally you can attach a but pad printed in TPE, insert pins cut from 1.75mm
Filament.

7. then attach the butt pad using the pins for alignment some super glue may be necessary


CLINTS M4 CARBINE PROP !49

 Attaching the Stock to the
Receiver
1. Press the stock onto the boss on the receiver firmly until it is seated all the way in.
Optionally super glue can be used for a permanent assembly.

CLINTS M4 CARBINE PROP !50

 Barrel Assembly
1. Slide the Delta ring down over the boss on the end of the receiver

2. Slide the Hand guard down over the boss and on top of the Delta Ring

3. Slide the Front sight onto the Barrel

CLINTS M4 CARBINE PROP !51

4. Align the slots on the barrel with the Holes on the Front sight and then insert the Front
sight pins to hold the Front sight onto the barrel and stop it from moving

5. screw the muzzle brake onto the end of the barrel


CLINTS M4 CARBINE PROP !52

6. insert a pin into the front sight post and then glue the front sight post onto of the front
sight using the assembly pin for alignment

7. slide the Barrel onto the boss on the hand guard. Optionally super glue can be used

CLINTS M4 CARBINE PROP !53

 Rear sight/Handle Assembly
1. insert pins cut from 1.75mm filament into the Rail Clamp

2. Glue the Rear Sight/Handle onto the rail clamp using the pins for alignment

CLINTS M4 CARBINE PROP !54

3. insert pins into the windage knob and glue it to the side of the Rear Sight/Handle using
the Pins for alignment

4. Allow the Glue sufficient time to set. using some clamps to hold everything tightly
together while the glue drys is a good idea
5. Place the Assembled rear sight onto the receivers accessory rail

CLINTS M4 CARBINE PROP !55

6. Place the Clamping bar on to the side of the rear sight and insert the Cross bolts

CLINTS M4 CARBINE PROP !56

7. Screw the Thumb nuts onto the cross bolts to hold everything together


CLINTS M4 CARBINE PROP !57

Insert The Magazine and test
everything
Insert the magazine into the receiver it should be captured by the mag catch and only come
out when the mag release button is pressed

Pull the charging handle using your index and middle finger, as you pull the charging handle
latch should move to unlock the handle and allow it to be pulled back just like on a real M4.
Pull the handle all the way back and let it go. It should snap back to its home position

The forward assist lunger can be pushed in and then spring back on its own. The Trigger
should be able to be pulled and spring back.

CLINTS M4 CARBINE PROP !58