This thread will be my first here in quite a while describing how I wanted to make a FSB cutout in a Noveske NSR.

My first thoughts about this project occurred back in 2012 when I was speaking with a friend about installing one in his Colt 6920 and I noticed that the way Noveske had milled out the top of the NSR.  It would be easy to locate a carbine positioned FSB by cutting the top at 7-9" and a couple of the vertical support pieces below.

This would mean the FSB could freely drop into the NSR.  It also meant the gas tube would have to be installed after the FSB was in the rail.  It also meant I would have to find a way to reinstall the taper pins with the rail around the FSB.

I'd seen Ayan (boltcarrier) mill out a couple of holes in a URX4 to allow taper pins to be reinstalled in a KAC barrel, but I didn't want to mill out both sides of my NSR, so my solution was to tap each taper pin hole with a 6-32 and install 3/4" long black setscrews.  Once I found this to be a workable measure, I probably removed and reinstalled them 25x.  I've also test fired this upper with them and they remained secure.  Once it's threaded, there will be a much more thorough workout.

Here are the photos of the up-close details showing how it went together.

The initial mockup



Removing all the NSR panels


Removing setscrews


Doing another mockup with an Anderson upper, which will be it's final home.  I'm using the VLTOR MUR in previous photos for a KAC E3 build which will be finished sometime in the next couple weeks.



If anyone has any questions, feel free to PM.

That looks badass. Great idea man, taper pins are such a pain in the butt. I'm definitely interested in seeing how the set screws hold up. Good work.

Really like how that turned out M4ger.

Was a fun project to discuss with you while you picked away at it.

The upper is finished now.

I got it threaded on 23APR2015 at Snipe Custom Arms in Lexington, Ky.

The PWS FSC-556 is a specifically designed brake which also accepts Yankee Hill 5.56 and 308 silencers.  The Ti762 which I have installs quite nicely also.

I'm going to function test tomorrow if the weather is good, as it is my bachelor party

Otherwise it will be sometime next week.





And installed on my Noveske gen2 SBR lower:

That's nice work man. Looks great.

Subscribing to see the long term report. Looks awesome!

I've been doing some shooting recently with various kinds of 223 and 5.56 and it has short stroked once and that was on Prvi .223 ammo I picked up at WM a while ago.  When shooting American Eagle 223 and 5.56, Federal 855, and PMC, it has run perfectly.

The FSB is still secure to the barrel so I think this setup is going to be a lot of fun in the long term.

The project turned out great! It does look bad ass.

I have a question, and its genuinely because maybe I'm missing something.

Why go to all the trouble to do this? (as opposed to just leaving the rail intact, and using a flip up buis, which looks like it would gain you another 1"+ of sight radius?)

If its, purely for the look, then, I will insert my foot back into my mouth, and carry on, sir.

I was just curious.

-Tim

I decided to do it because sometimes you just have to see if the idea in your head can be made real.

There are only a couple keymod rails with the design to allow a FSB through, and with the pedigree of parts on this upper, I decided the Noveske was the way to go.  I know using the KAC M4 barrel and making it 11.5"

I may do the same thing with one of the EraThr3 handguards. in 13.5" length on a 14.5" build.  I only need to get one first so I can compare it to a FSB equipped rifle and see if that works out.  That won't be for a while though.