Words and Pics: @Milsimminded


Back in the day – before I knew about reenactment – I started a PTW build that was entirely based on what I thought was cool at the time. Basically it came down to a Mega Arms receiver, a CMR rail and random parts that appealed to me. Then I got introduced to the Milsim scene and accordingly, reenactment. The civilian rifle started to stick out like a sore thumb.

After I got serious with the CAG loadout, I bought a HAO HK416D V2 kit. At that point the civilian build was relegated to a backup rifle. However, even if my 416 was in for maintenance I would simply refuse to pick up the civilian rifle, since it would just undo the look of the whole. So, I thought it was pointless to have it around. I would either have to sell it, or transform it into something I would like to use; which meant another military clone build.


I was thinking of going for a second CAG 416 (in 14.5), but then I thought it would be a hassle to get the look right. I had no need to go carbine length, so I would just build a short 416 identical to my current one…

Then I started playing with the idea of doing another complete loadout: US Army Special Forces (SF) – which I’m currently building. That meant an M4A1 Block 2 build to accompany it.

Most reference pics show the use of 14.5 inch carbine uppers, but that length has no functional benefit for me. While the CQBR is spotted less often, it was still popping up from time to time – so I decided to go that route. SF are, after all, issued with long and short uppers.

Reference Pics

The following reference pics really influenced the build, although bear in mind they’re not all Army SF. I initially cast my net wide, took in all the variables then boiled it down.

Build Philosophy

I believe that In order to get an impression ‘done right’, all parts must feel real – not just the lid and nylon hardware. If the gun looks or feels fake then it devalues the rest.

Many gun parts are now cloned and some like HAO and Zparts’ products are almost – if not entirely – identical to the real thing. However, I decided to up the stakes and go for a build containing as much real steel (RS) as possible. The Systema PTW – of course – is still the best platform for this, balanced with its high performance on-field capabilities.

So, I tried to source as much RS as I could get my hands on. If not possible I went for the very best alternative – such as the Zparts receiver, which is the most authentic looking M4A1 receiver set out there in my opinion.

I also tried to use the paint guys use in the wild, burning some spots to make it look more used; all the small details to get the feel right.

As for how I decided to set up my rifle, I went with the philosophy advanced in The Reptile House article, “By Numbers – a discursive piece I’d really recommend reading. As I am pursuing an SF kit, I wanted to make the M4A1 as personalised as possible, while staying within the realms of what’s believable. This is in stark contrast to how I would tackle a Ranger M4A1 or my still unfinished CAG 416.

Parts Collation

In Belgium it’s harder to source RS than in some other European countries. So I enjoyed the help of some kind friends to sort me out with the good stuff. Other then the actual Colt parts, I had to look for the B5 stock for a while. The Daniel Defense RIS II was also a search, but after a few months with the help of my friends I got everything I needed.

The receiver was a big problem at first. Ironically, I had a lot of the RS components already in, but I was awaiting HAO to restock their Colt M4A1 receiver. It never happened. In the end, I was forced to look elsewhere. I stumbled upon a high end brand I previously did not know, which is really gaining traction in PTW-world: Zparts.

I was a bit hesitant at first, but after seeing detailed pics of their M4A1 receiver set, I went for it. I was amazed by the quality of the receiver! It’s forged, like the real thing, and has the best stamped trades I have ever seen. The ano is also excellent and really tough.

And just look at that beautiful forge seam! Just like the RS!


So, I tried to use as much issued stuff as possible, blending in some rare and older kit to give the build a bit more depth – for example the old gen Surefire M600V. The ladder covers are also a thing I like personally, but are rarely seen.

One early liberty I took was the Wilcox FTS in tan. I previously thought it was kosher, but I’ve only spotted the black one with SF. So I ditched entirely. Some stuff I added was just experimental, or served as a placeholder. For example, I cut down a Magpul RVG grip in place of the Tango Down stubby grip I awaited.


For the paint I used Krylon Sand. It seemed to match in the wild pics and being a US brand I felt I was on safe ground. I masked off the magwell UID in a nonchalant way and just had at it – after degreasing and protecting some of the PTW’s paint-sensitive internals.


I’ve got loads left to do with the M4A1 and there will be incremental updates as I progress, but I feel this is a solid V1.0.

Next, the gun needs a trip to the UK to be fully Tackleberried. While it’s there, Tac will fit the remaining RS parts I’ve been unable to fit – including the Ergo 2 grip.

Parts List

Systema internals and small parts (aside from those listed below)

Zshot Colt M4 receiver set

HAO 10.3” aluminium barrel

Airsoft Artisan Surefire four prong flash hider

HAO and Airsoft Artisan Surfire suppressors (HAO is way superior, but real weight)

Systema pistol grip; nub ground off ghetto style (soon to be replaced with an RS Ergo 2)

Systema forward assist (soon to be replaced with RS Colt version)

Generic front and rear BUIS (to be changed when I find an RS set)

Generic low profile gasblock (needs to be changed for an RS DD one)

Unique mag well UID tag

FMA Lab UPH (needs to be changed out for an LA5)

RS Colt dust cover

RS Colt charging handle

RS Colt castle nut

RS Colt buffer tube; modded for PTW

RS Daniel Defense RIS II FDE

RS Tango down short vert grip

RS Larue LT 101 ⅝ riser

RS Eotech EXPS

RS B5 LMT stock

RS VTAC MK2 padded sling; old gen

RS Ferro pull tab

RS Surefire RM45 mount

RS Surefire M600V; old gen

RS Surefire dual switch

RS CQD forward sling mount

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