Words and pics: Rich Norman


It took a while to get there, but my AFSOC-inspired “Transitional” M4A1 refresh is done. Needless to say, it’s enjoyed the usual Tackleberry magic. This includes an Armour Black Cerakote paint job for the receiver, which brings the finish of upper and lower closer to that of the authentic Colt.

Visually, at least. Cerakote is, after all, paint – not anodising.


With any build, there are always Rubicon moments, and this one was no different. The Cerakote choice itself was one of them.

Firstly, did I want to go black or grey? There’s a lot of variation in the wild, so I decided my best bet was to go with what I preferred; not make it an academic exercise.


Drill down a bit more and there’s an additional dilemma, however.

It’s long been observed that on closer inspection, many plain M4 receivers seen in the wild aren’t of uniform tone between upper and lower.

One explanation for this is that the upper is treated as a consumable. It’s a service part, which is replaced according to wear and tear – basically how many rounds it’s had through it.

The lower, on the other hand, can remain constant for years. AFSOC is a good example here, because their lowers are often used for decades. It’s not uncommon to see XM177 lowers on their “M4A1s”, for instance.


So, the question was, did I want to go for a subtly different tone between upper and lower? I decided not to – I wasn’t feeling bold – but I wouldn’t rule it out for a future build.

The rail was also a big deal, which resulted in me acquiring both an RS Daniel Defense Omega 7.0 and – through the kindness of a friend – another KAC RAS (I’ve had a few, but never used one in a build).


So here’s the thing: I really, really love the look of the classic Block I M4A1 carbine but equally I really, really love a twist on the original.

And here’s where the concept of the Transitional Blaster comes into play – Block 1.5 in this case; an unofficial, bottom-up, upgrade package between Block I and Block II.


There’s an excellent article on Taranis Blog, written by fellow blogger, trusted contributor and – crucially – friend, Jay. It’s about his awesome SFSG L85A2.

In the article Jay persuasively articulates the lure of the Transitional Blaster, and it is essential reading – I can’t imagine any Reptile House readers not subscribing to Taranis Blog, so I’m probably preaching to the converted here.


The other advantage of the DD Omega over the KAC RAS is that it’s free float. Because I already knew I wanted an aluminium outer barrel on this build, I couldn’t risk putting additional strain on it by using the RAS.

It’s not an accuracy thing, but one of robustness. During a catastophic event – like running into a brick wall – I don’t really want to end my game by bending the barrel, when I can protect the first 7″ with a free float rail.


Also, the Omega has integrated rotation-limited sling points, is easy to install, and provides an almost continuous top rail (there’s a slight gap to allow for heat expansion in the RS).

It’s all about the details and as usual a parts list follows.


I’m really pleased with this refresh. The AFSOC-style form factor is twist on the classic Block 1 M4A1 and the handling is sublime, thanks mainly to the HAO aluminium outer barrel.


What’s left to upgrade? The LA-5 clone is just a prop I keep around for pictures, I don’t use one in-game. As such, it’s not something I’m looking to replace with RS.

A Surefire light (RS or replica) would be great for pics, but isn’t a lot of use at the local woodland site I’ve been known to inhabit. I do have an FDE Surefire RM45 mount I’d like to use, though.

The Aimpoint Micro H2 isn’t quite right for Block 1.5. In fact, it’s totally anachronistic.

And herein lies another conundrum: do you go with a product which isn’t picture perfect (but which is likely superior) or do you go with a replica that *is* picture perfect (but which is likely inferior)?

I make no judgement on this, but I’ll hopefully be teasing this out with some trusted contributors in a later blog. Both viewpoints have their merits, depending on your position.

All that said, the Aimpoint Micro H2 is the best optic I’ve ever owned.


The only thing I would replace – funds allowing – is the receiver set.

If I had the money spare, I’d go with HAO; but Prime is fine – particularly with the Cerakote finish – and I’ve had this current set for a good few years now.

Why am I not gushing about Prime? Well, it’s mainly to do with the mag well. It’s wider than the OEM Systema and the distance from the mag catch to the hop is a tiny bit shorter than it should be.

The result? Some mags have to be very firmly seated to lock-in. Not a problem with the Tackleberry Super Float Pmags that I use, but worth mentioning.

This, plus the HAO is a much better product; better tolerances, better materials, better trades, etc.

Roll on HAO L119A2.


Parts List – with links to more detail on the blog:


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