It’s rare that a planned upper works ergonomically first time – for me, anyway. Usually I go through several iterations before it’s right. This try, however, I got something that works really well straight off the bat.

Aside from a smidgen of my own judgement, I owe my luck mostly to the USASOC URG-I pics that influenced me and make this upper a loose clone.

Most influential was this pic, which I blogged about previously:

USASOC URG-I reference pic


After finishing my UKSF L119A2 clone, going back to USSOF stuff has given me a freer hand. Discipline and scrutiny are effective motivators and there are scant few scenes more disciplined or scrutinised in the AR replica world than that of UKSF clone rifles. It’s a huge strength, which can also be a weakness.

The bar is set high and the slightest nod of peer approval can only be achieved through exacting standards. On the other hand that exactness can stifle innovative setups. I circumvent the latter by having two L119A2 configurations – both of which work for me ergonomically, with one more conducive than the other. However, while one is a reasonably strict clone, the other is relatively out there – so can’t really be called an L119A2 at all. You can guess which one I prefer for actual use and, conversely, which one I prefer as a wall hanger (and thus feature mainly in the blog).

Back to US clone rifles and in comparison to UK stuff you get to choose from a lot of the more interesting accessories on the market today, for a truly custom and aesthetically pleasing fit. That’s because there’s more and varied cutting edge stuff in use, due to the sheer scale and/or budget of US specialised units (plus many other factors, cultural included). What this translates in to is that if you want to use something cool, there’s more than likely documentary evidence to support it.

With all that said it’s as possible to approach a USSOF build with a more fundamentalist mindset, but that’s not the view I’m taking here. Also note that the lower featured is merely illustrative. It’ll be replaced by an M4A1 lower, based on Systema’s new Infinity platform.

1. Laser, Light and Angled Grip Combination

Most surprising in terms of first try ergonomics is the light and laser combo up front. I was hoping this configuration would work, but I was expecting to have to think again; because, so many times the position I want the light in conflicts with the laser’s location up front.

Aside from the light and laser not interfering with each other, which largely is down to the spacing of the excellent Reptilia Light Body (the right sided version, but used on the left side of the rail), everything is operable using my support side thumb because of the beautifully CNC’d Railscales Anchor.

Think aluminium VFG, AFG or hand stop and you may think cumbersome. Neither is true here. The Anchor is svelte, light and amazingly ergonomic. It allows decent reach along the rail and a neutral wrist position for the thumb over bore handling technique. The Anchor is actually bi-directional with a choice of flat or angled surface, but the sloping face up front works best for me.

2. Sling Mount

Another Railscales item that makes its debut here is the QDX Sling Mount.

Again, it’s beautifully machined from aluminium and is sturdy and light. It’s also bi-directional and can be used with a range of sling hardware. Here I’m using a Ferro QD (REVIEW).

Just to add that this is my first proper brush with MLOK and I’m sold.

3. Optic and Mount

The Sig Sauer Romeo 4T made famous by one Christian Craighead (or Obi Wan Nairobi as he was dubbed before going public), is now a feature of CAG blasters. It delivers an EOTech style reticule in an Aimpoint Micro style form factor and really is a great little optic.

I’ve written at length about the Unity Tactical FAST Mount – the ergonomic upgrade that’s not just for NODs (REVIEW). Suffice to say I won’t be going back to lower third any time soon; not by choice anyway – although obviously my L119A2 clone config still has a bog standard Aimpoint mount.

4. Charging Handle

Lastly, the charging handle is of course the Geissele ACH. However, this is the non-clone version, without roll marks or part number as that’s all I could get in the UK unless I resorted to a copy.

Parts List

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