DIY: aac's M67 Dummy Grenade Upgrade Project

[aac]

1.0 introduction

Everyone has probably came across those dummy grenades on AliExpress, and Airsoft stores and actually wondered what good there actually fore? The functionality is 0, and with the exception of a nice gadget  completely useless.

When doing research on foto's I've spotted the M67 frag grenade on the Warbelt of SOF operators a few times, and actually i think this is quite a dramatic-looking detail.

And below on the iconic Delta photo

 

2.0 M67 History
The M67 is at best a dated concept, it is a further development of the M33 grenade (which looks almost identical) and which came into use in the late Vietnam war years, The M33 on was the successor of the M26 grenade which on its turn was the successor to the iconic Mk2 Pineapple grenade from WWII.



2.1 The M67 Specifications
Is a so-called fragmentation grenade, with a spherical body, therefore it is also called the baseball grenade, it contains 180gr of explosives, and weigths 400gr in total, the M67 can be thrown about 30 to 35m far, explodes with a delay of 4 to 5.5 seconds, has a radius of 15m, and a lethal radius of 5m.
https://en.wikipedia.org/wiki/M67_grenade

2.2 M67 operation
Such a fragmentation grenade consists of 2 main parts, the charge and the fuze.

The Fuze contains a striker (hammer) which is under spring tension and is held that way by the so-called Spoon (spoon) which in turn is held by the safety, and the jungle pin, when thrown and the spoon released, strikes the striker on the primer (percussion cap) which after a delay finally detonates the main charge.

2.3 Jungle clip
The Jungle clip was an extra security which was developed during the Vietnam War, after several grenades had accidentally gone off when the safety pin was pulled by branches!

The pictures below make the operation more clear i hope





2.4 M67 looks
I then took a closer look at those grenades and how they actually look like in reality, and so it quickly became apparent that those dummy grenades really look as toys.
Hand grenades are mass-produced , and finished in a not-so-fancy finish, the body is a raw, cast-iron ball, the Fuze body, high-pressure, formed aluminum, and the Spoon pressed sheet steel.
These grenades are also only finished with a thin layer of paint, instead of durable coatings I think ?

When these are worn unused for a while on soldiers in the field, they can get a bit dusty and weathered after a while.

 

And so I finally got the idea to get such a dummy M67 myself, and pimp it until it would start to feel and look a bit more real.

2.5 tactifans
I got my M67 dummy from tactifans on Aliexpress, a nice shop where I also got the QR Cummerbunds for my AVS, and the legstrap for my TMC354 do holster.




3.0 The upgrade project

3.1 Fuze Gasket Ring
Was the first part  that I made, altough no more than a ring between the fuze, and the body, nevertheless an important cosmetic detail, I made it from stainless steel and let it stain in a gas flame to give the patinated effect of the real approach ring.




At the same time I removed the aluminum ring that is around the plastic neck of the dummy grenade, this serves to reinforce the (very thin) neck against bursting open, but it looks terribly fake!



3.2 Ballasts
The first thing you notice when you hold the dummy M67 is the weight, barely 60gr!  Something had to be done about that, since the real M67 weighs 400gr.
With some old steel balls I could easily approach this weight, to prevent the grenade from becoming a kind of Tic-Tac rattle box, I filled it with silicone at the same time to make it stick together, immediately a world of difference!

3.3 Body Drybrushing
To make the plastic body look more like weathered steel, I drybrushed it with aluminum paint.

Drybrushing is a model building technique in which you first dip your brush in paint, and then wipe it clean on a tissue, with the remaining paint in the brush, you then drybrush the surface (that you want to treat), the paint will only attach on higher areas and edges.

Ideal about this dummy M67 is the bumpy surface structure, which quickly made the plastic body look like a steel one.

3.4 Fuze Body paint job.
The Fuze of the dummy M67 is made of plastic and sprayed in a shiny aluminum paint.
Real fuze bodies are repainted in some sort of OD, so I did the same with the dummy fuze.
To approach the translucent effect of the real M67 fuze, I actually dusted the plastic fuze , and almost immediately wiped paint off the edges with tissue dipped in white spirit.

3.5 Striker Pivot Pin
You can clearly see this on the real M67, it is the pin where the striker hinges arround.
On this dummy M67 there is only a hole! (The recess in which the striker is located is not even provided) But luckily it is easy to fix.
Took a steel 4mm rod, sawn to length, and punched in the small cups (like the real ones)  painted into flat black, easy and instant realism gain.

3.6 Spoon and Safety clips
These are already made of steel, the Spoon is painted in OD. Just like on the real M67
I spray painted the pins and ring in the same Nato green as the fuze body.
Then I put all these parts in a closed plastic jar, along with some sandpaper strips, and screws, and gave it a good shake, to make the sprayed parts look a bit more weathered, 
finally weathered some extra accents on corners and edges applied with a file, and done.

3.7 Assembly

And so all parts were individually ready and it was time to reassemble everything.

Striker pin slid into the fuze body, spring inserted, Spoon fitted and secured with the Safety, and Jungle pin (so you can indeed make the Spoon jump away when you remove the safety pins, since it is under spring tension)



3.8 Dusting
Was the last trick I wanted to apply to give the M67 a more realistic, dusty look.



This is also a model building technique, here you first scrape pastel chalk into a powder in the desired color, and then you apply this using medical alcohol, here you have to let the powder flow with the alcohol in the desired corners, and over surfaces, when the alcohol evaporated, only the colored powder remains, where not desired or too much, you can easily wipe it away.

Pastel chalk at Action for little, alcohol also not expensive, the technique itself is not difficult, and the result is very realistic.

3.9 Graffiti
Can be seen sometimes on real grenades, and I do like it as a nice dramatic detail.

So much so that i decided to add also a text on my dummy M67 with a marker



View my full dummy M67 upgrade project photo album here

[shmook]

Lovely write up and really well done 🙂

[aac]

Thx dude, its really a funny project tot do, i recommended it  😊