A good mate is planning a gucci Block II build, inspired by Tan_Rifle’s awesome blaster:
So, out of interest, I started looking through reference pics of modern USSOF M4s to see what’s trending in terms of personal purchases.
The first place I always look nowadays is @btl_ltw (Born to Lose, Live to Win).
One thing that really struck me was the obviousness of the Magpul MOE SL range of stocks – in particular the SL, but also the SL-K.


As far as US elements are concerned, I’ve only really been looking at CAG stuff recently and in public pics there’s not a huge variation in their stocks – sticking, it seems, with older designs like the LMT/B5 SOPMOD stock and the Magpul CTR. Both great stocks – classics.
So, part of my surprise is how much more progressive the non-CAG guys seem to be with personal purchases. Obviously there are a lot more of them (Army SF, for instance, is huge) which is a factor.
The Magpul MOE SL (or Slim Line) is the standard version of the stock – the successor to the Magpul CTR. The K is the compact version, ostensibly for shorter blasters.
Magpul has a series of excellent videos explaining their current stock line up, with this one explaining the non-storage SL types:
The presenter talks fast, which is great if – like me – you find most YouTube reviews ponderous.
Of note in the SL line’s spec is that it’s optimised for use with body armour; incorporating a rolled toe at the base of the butt pad. The K also benefits from a greatly reduced butt contact area, which helps it fit above plates.