ive seen all sorts of  "M4s" posted here.  some with jagged ended flash hiders, rails covering the handguards, optical sights, peep sights clamped on the upper rail and all manner of stocks...

the only M4A1 ive been involved with has a flat-top with carry handle and A2 sights, the M4 profiled barrel and an A2 flash hider.  it of course has the collapsable stock and the selector goes from safe to semi to auto...





david

I think many, if not most of us have been in the military and played FA.  Some people still have the FA bug, some don't.  

I'm curious as to why your issue M4 is missing the M68.

Here's a pic of one of my training ones that I teach with.  I don't use an optic when I teach classes, I use an Eotech on my duty carbine.

what kind of M4geries are you guys building?

I've been putting together a full-auto M4A1. I started with a registered M16 lower, added a 14.5" Colt M4 upper, an Aimpoint ML2 in an ARMS #22M68 cantilever base, ARMS #40 BUIS, and a registered SRT Hurricane sound suppressor. I still need to add a LMT Crane stock to complete the M4 transformation. Then I will still need to add a railed handguard and vertical grip to finish it off completely.