I finished two builds this past week, and got a chance to take some photos this evening.

One is my version of an Early XM4.  (The other is my XM177)

I'm not quite sure what put this particular bug up my butt.  I guess it's because I had a 723, and a SOPMOD Block 1, and it felt like there was a gap to fill.  It's been a couple of years collecting parts and daudling, but I finally got the last piece of the puzzle, sending the barrel off to John Thomas.

John took a standard M4 barrel, and turned down the area between the FSB legs and in front of the FSB to match up to the M203 notch.  This was done to clone one of the prototype barrels that had drawings in the Black Rifle II. (image included below).  He parked it all again, and remounted the FSB, and it all looks great.  Highly recommend his work, as everyone else does, always.

The rest of the build:

• Nodak Grey A2 Lower - Nodak (Of Course)


• Colt Grey A2 Upper - Dennis


• Del Ton 16" M4 Barrel - Del Ton (modified by JT)


• Colt Grey Delta Ring - GenoFromReno


• Colt 4 Position Buffer Tube +H Buffer/Spring - GripnAK47s


• Colt N1 Fiberite Stock Boddy - CrazySarge16


• DPMS LPK - Midway


• Colt M16 BCG - BoyWonder777


• Colt Grey Charging Handle - Gunnor

Big thanks to all of the Arfcommers that helped this and all my other builds over the years.  You guys are great.
And a major thanks to JT for doing the barrel modifications, and making everything silky smooth.  It looks better than I could have hoped.  You're amazing, as always.

Ok, ON TO THE PHOTOS!

The full gallery with more and larger photos can be viewed here: https://www.flickr.com/photos/nduguid/sets/72157686707088534








Here's a shot of the diagram out of BRII (Pg 72).  I went with the middle design:

Great job!  First one I have seen like that.  The front of the barrel ends up similar to the Colt Canada C8A3 barrel.

Range Day! I didn't have a ton of time, so I just got them on paper and shooting straight.

I kinda like that barrel profile...  but I'm wondering what it would take to make one like the top prototype...  

The top is essentially what all of those pseudo "lightweight" profiles out there are, where the area in front of the FSB has been turned down, but the FSB itself is still on 0.75"

Correct. I believe that is the same profile as the Diemaco C8 from Canada.  JP enterprises used to sell a similar profile with the .750 gas block profile.

Any reason you didn't make it 14.7" pinned?

Looks great otherwise.

That's the main thing I was looking for on an XM4 build.

I know everyone's always giving me shit for using 16" barrels. But I really dislike pinning/welding, and avoid it whenever I can. I like everything to be disassemblable by me. I pinned/welded my XM177, because that was 4.5" I didn't want to add on. But an inch and a half?  I'm fine with that.