1.0 The New Build

I haven’t been this excited about a build since I received my first Systema PTW from Tackleberry in 2010.

He’s looked after all of my builds since then, but the L119A2 is the one I’ve been most invested in.

The project started over a year ago when I received HAO’s Beta Release L119A2 IUR (Integrated Upper Receiver – or monolithic upper) as a review sample. However, the foundation of this L119A2 is HAO’s highly comprehensive L119A2 Full Kit.

Released in June 2019, it features a revised upper as well as all the parts required to build a PTW-based L119A2.

Although HAO bundles exceptional replicas of the correct Colt Canada parts with the kit, I acquired the genuine items where I could.

While HAO and the RS items I gathered provided the building blocks, a Tackleberry build is more than just the sum of its parts. That’s why I’ve trusted him with my PTWs for the past nine years.

There’s just one catch: the wait on scratch builds is long and sometimes it seems like there’s no end in sight. But it’s worth it when your PTW finally arrives!

I always recommend going with Tackleberry’s full range of performance upgrades. It doesn’t just stop with his well known hop mod and motor rewind. There’s a whole portfolio of modifications which, when combined, offer the gold standard in out of the box accuracy and reliability.

Aside from PTW mods per se, I would also highly recommend acquiring a set of Tackleberry’s Super Float magazine conversions. Suffice to say, in my opinion, they represent the most effective PTW upgrade external to the rifle itself.

2.0 Build Configuration

This section sets out my rationale where I’ve made decisions about build variables, e.g. where there is customisation, a choice of parts, or where peripherals are located.

2.1 Ghetto Modded Ambi Charging Handle Latch

I worked with Tackleberry on a full list of requirements, for taking my L119A2 from a collection of parts to a personalised turnkey solution.

These requirements included customisation options, an example of which is the work he carried out in ‘ghetto modding’ my RS Colt Canada ambi charging handle latch. Read more about that here.

Basically, the mod makes the latch less liable to hang up on stuff.

It’s commonly seen in the wild and appears to be a user preference. I don’t think there’s any right or wrong way to do it, but Tackleberry interpreted the reference material I provided to deliver something which perfectly meets my needs – and looks good, too.

2.2 Magpul MOE K2 Grip

In terms of ergonomics, I decided as soon as I tried Tackleberry’s Magpul MOE K2 grip conversion for PTW that I couldn’t be without one on the L119A2.

This isn’t a cheap option due to the labour required on the motor alone, but as an ergonomic upgrade it’s become an essential on my builds rather than a nice to have.

The K2’s steeper angle completely transforms the biomechanics of rifle handling (along with commensurate stock adjustment and foregrip selection/location).

For me, this ergonomic aspect far outweighs my admittedly heretical deviation from the Original Ergo; which is the factory L119A2 grip.

That said, I believe the K2 to be a reasonable alternative because: 1. it’s significantly different in terms of functional utility when compared to the Original Ergo; 2. in the RS it’s really easy to fit, as all grips are; 3. it’s easily sourced; 4. it’s inexpensive; 5. it’s a Magpul product and everything points to Magpul products being popular with UKSF.

As luck would have it, the K2 suits this build aesthetically.

2.3 Magpul ACS Stock

I originally tried out the build with my trusty Magpul CTR (the L119A2 factory stock) but found it lacking in this implementation, when compared with the Magpul ACS (also seen in the wild). In part this change has something to do with switching to the K2 grip.

Of note is the position of the stock on the receiver extension. It’s further towards the receiver than is usual for me, because of the K2 grip. This keeps the A2 close to my body and makes it easier for me to manipulate.

The ACS is longer than the CTR or STR, so is better for those of us who benefit from a longer – as well as wider – cheek rest.

Black or FDE was a tough choice, with only black being verified in reference pics. I bought both, but went with FDE as I thought it looked better with my other parts.

2.4 GG&G Vertical Foregrip (VFG)

Over the years, I’ve gone from bare rail to AFG/AFG2 to handstop to VFG and back round again any number of times. I can’t guarantee I won’t do it again. However, like Dean’s sage words in this article, I can pull the rifle more effectively into my shoulder with a VFG.

A VFG also gives me the option to switch from C-clamp to broomhandle grip and use a clicky end cap on my light – I’ll explain why below.

The choice then is between using a full length, 90 degree GG&G VFG or an angled, stubby BCM VFG. Both are legitimate choices, the former being seen in reference pics and the latter confirmed in use by The Geardo Crow in this article.

Unsurprisingly, I bought both the GG&G and BCM to try out.

Since I have massive hands and want to grip broomhandle style as well as C-clamp, the GG&G is the better choice right now. The BCM is really too short for me in broomhandle mode and the profile doesn’t lend well, either. It does make an excellent handstop/C-clamp grip, however, so is well worth considering for that application.

2.5 Surefire M600DF Scout Light

I prefer to use a thumb operated clicky end cap with the M600DF Scout Light rather than a remote switch. This can be accomplished in my configuration by changing grip from C-clamp to broomhandle (hence the use of a VFG as mentioned above).

Various M600 and M620 series models are thought to be in use with UKSF in tan and in black, so a tan DF is a low risk choice.

2.6 Surefire RM45 Scout Mount

There does not appear to be a huge amount of variety when it comes to light mounts. Indeed, so far the only aftermarket mount which is widely accepted as legit is the Surefire RM45L – as used by Obi Wan Nairobi.

Most reference pics exhibit OEM clamps of the type bundled with either M600 or M620 series Surefire lights. There is also one pic which seems to suggest direct mounting is a thing.

Taking all this and my idiosyncrasies into consideration, I chose the M600 counterpart to the M620’s RM45L.

It puts the light right where I want it for trouble free activation.

2.7 Manta Momentary Switch Rail Panel

This rail panel effectively secures my LA5 remote switch.

It’s positioned so that I can activate the LA5 (and nothing else) while I grip using the C-clamp method.

Manta stuff is a safe bet as far as UKSF are concerned, with this unit turning up in at least one pic.

2.8 Magpul MS3 Sling, Magpul RSA and Magpul ASAP

This groupset of Magpul components needs no introduction. The Magpul ASAP itself is the factory L119A2 rear sling attachment (as far as this A2 version is concerned – read more about L119A2 versions here).

Equally, the Magpul MS3 and RSA are both listed in official documentation as part of the L119A2 ecosystem, with the MS3 identifiable in the wild.

Robust credentials aside, I think the MS3 is the best sling I’ve used and you can read my thoughts on it here. In short, the chunky slider is really easy for me to manipulate and the combination of Magpul Paraclips and stiff 1.25″ webbing means no tangles. Use of Paraclips also means ditching the rifle is easy, as is transitioning from two to one point.

As far as placement is concerned I’ve tried all sorts of permutations – not just on the L119A2 while I was dialling it in, but on previous builds. Currently I get on best with the forward sling attachment placed behind my support hand; and the rear attachment point not on the stock, but at the rear of the receiver (with the ASAP being the perfect choice of adaptor for ambidextrous use).

2.9 Sig Sauer Romeo 4T Optic

While Obi Wan Nairobi was the catalyst which made me want to buy this optic, the 4T offers real functional utility for me.

It combines the Aimpoint Micro’s weight and form factor with the usability of an EOTech reticule; i.e. the optic is small and light, and the reticule doesn’t turn into a comet like a red dot can do for those with an astigmatism (like me).

2.10 Jay Taranis’ UKSF Spec Label Kit

This is an absolute essential for turning your LA5 into an authentic-looking UKSF spec item. Even guys with real LA5s use these stickers.

I’m not the best at cutting out shapes with a scalpel or scissors, but applying these stickers makes a huge difference to how my LA5 looks. In one sheet, you get two instances of each of the three labels required.


3.0 Optional Finishing Touches

What’s next? A couple of options are open to me.

3.1 Suppressor

Ideally I’d like to procure HAO’s forthcoming replica FA556SA suppressor, but if the wait is too long – or if it isn’t of close enough spec – I’ll decide between my other options.

Angry Gun has already released its version of the FA556SA can and FH556-216A flash hider. I hear they’ve done a decent job and at their usual price point.

Airsoft Artisan is soon to released its old gen FA556SA can (seen in the wild), which I’m told will be compatible with Angry Gun’s FH556-216A flash hider. I think that’s also worth a look before I make any decisions.

Lastly, there’s Bruno’s excellent 3D printed FA556SA all in one solution which – for a mere €25EU – is incredibly detailed, light weight and a steal. This could be the best option while I wait to see what HAO does.

3.2 Paint

My original idea for paint was to go Kryptek, but since my friend John has famously raised the bar out of reach with his own HAO L119A2 PTW, I may do something different.

We’ll see…

4.0 Build Parts List


  • RS Colt Canada trigger guard
  • RS Colt Canada six position receiver extension
  • RS Colt Canada receiver extension nut
  • RS Colt Canada ambi charging handle assembly
  • RS Colt Canada ambi mag catch assembly
  • RS Colt Canada ejector port cover assembly






  • RS Manta momentary switch rail panel



  • RS Surefire M600DF scout light
  • RS Surefire RM45 scout mount

More articles about the real steel UKSF L119A2:

  • The Comprehensive UKSF (SAS/SBS) L119A2 Parts and Accessories List
  • The original L119A2 primer, here
  • GG&G AR15 vertical fore-grip in use here
  • Magpul QDM and ASAP QD in use here – part 1
  • Magpul QDM and ASAP QD in use here – part 2
  • 15.7″ L119A2 upper in use here
  • Surefire FA556SA Suppressor here
  • GG&G Aimpoint T1 mount in use here
  • Magpul MS3 sling in use here
  • Magpul ACS stock in use here – part 1
  • Magpul ACS stock in use here – part 2
  • Colt Canada parts – as used on the L119A2 – here
  • Manta Very Low Profile Rail Covers here
  • S&S Precision Sling Clip – Old Gen – here
  • Inforce WML-type lights in use here
  • UKSF Manchester UK incident video here
  • UKSF Manchester UK incident L119A2 here
  • UKSF Newcastle UK incident part 1 – here
  • UKSF Newcastle UK incident part 2 – here
  • UKSF Nairobi Kenya incident L119A2 parts breakdown here
  • UKSF Nairobi Kenya incident Proctor Way of the Gun Sling here
  • UKSF Nairobi Kenya incident LaRue RISR here
  • UKSF Nairobi Kenya incident Surefire RM45L M620 Scout mount here
  • UKSF Belize ‘Jungle Set-up’ L119A2 parts breakdown here
Obi Wan Nairobi patch from Platatac

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