I was looking at putting on a 10" rail system and read about shavin the FSB off making a low profile gas block. The problem is; that I’ve yet to find any photos of this done. So if anyone has this done this and has photos I would appreciate it.
Here’s what you’re looking for; https://www.m4carbine.net/showthread.php?t=6099
Here’s a ‘shaved’ one I just did on a 14.7" barrel with perm. mounted A2 flash hider (CMMG barrel). I’ll be mounting a 9" or 12" Omega rail on it. (customers gun). I had to go ultra low on this one. It’s in the raw, I need to clean it up and hit the whole thing with some flat black Norrells Moly.
You guys make it sooo tempting to do. Suppose the only thing holding me back at this point is the sale of the current 7" D Omega so I could get a longer one…
I shaved my gas block to to fit under a Larue 12.0, and it was a major pain in the butt. I’m pleased with the end result, but it was a lot more work than I anticipated. I don’t know about other designs, but the LT rails are not very friendly with non LT-gas blocks, it seems.
It turned out a lot like the one GotM4 posted but not as nearly as pretty :o
gotm4, you had to work that one on the barrel then?
Yep. It’s a lot harder.
That was what I really wanted to know, was it possible to do with it still mounted. I think I have a project ahead of me.
Here’s a pic of one I’ve done to fit underneath a LaRue 11.0. It wasn’t fun, but it didn’t take too long, esp since I’d already done a few before this. It isn’t pretty either, but since it’s underneath a rail (and the rifle is painted), looks aren’t as important as function.
Now if I could get one of you fellow to do all the work I’d have it made. 
I too like to shave the FSB to make my own gas blocks. It can be done on the barrel, but it’s a minor PITA. Off the barrel it can be performed very quickly with a belt sander & Dremel tool. And, yes they can fit inside a Larue.
Just a shameless plug - GotM4 shaved down the FSB on my LMT upper in order to accommodate a LaRue rail, which he also installed. His work is excellent, and I recommend him and Virginia Arms to anyone in the Northern Virginia area.
Big +1 for Gotm4, and Virginia Arms.
He did my SBR, and I live in Vegas!
Thats how I did mine. I did it on a grinder, it dosent have as nice of a finish as gotm4’s does but it did turn out uniform.
i’ve done one myself, it wasn’t that bad.
but the last job that i sent to ADCO, i threw a FSB in the box and they did it for $30 (and it looks way prettier than mine).
another option is to cut the rail this is one I did and it turned out well
I ended up having to take more metal off the the FSB, it was still contacting the Omega rail when I installed the rail over it. I shaved it more and this is what it looks like after refinishing with Norrells. The guy who’s upper I’m building is still undecided if he wants a 9" Omega or a 12" Omega. 12" would look bad ass on this as it’s a 14.7" barrel.
Yeah, what’s the story on that? It’s 14.5 so he doesn’t want to remove the flash hider, thereby making him “stuck” with the Omega?
That’s a hell of a shave there Robb. You clearly have more patience than I do. Hell, I now have a nice new lower all dinged up by my brass mallet because I got too impatient banging in the bolt-stop pin. :eek:
It was pretty time consuming. He wanted the shortest lightest possible barrel (non carbon-fiber) that he could get without having to get a tax stamp. It’s a 14.7" CMMG 1x7 twist with perm. mounted A2 flash hider/comp.
A 12" Omega is going to look amazing on that. I ended up going with a 14" Lite Rail on my 14.5" upper and it looks a little excessive, but I’m going to give it a go. I didn’t have the patience to shave it down far enough to fit the Omega on it. I got tired of near catastrophe at the grinding disk.