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Suicycle
10-23-12, 17:07
I have browsed the sticky threads and read a few pages of info but I am new to working on this platform. Not absolutely sure my FSB has taper pins in it, I know how to identify just haven't done it yet. I am thinking of cutting down to make a low gas block so I can mount some form of free float rail. I don't need tons of rail so I am looking at Sampson Evo, Diamondhead, or MI gen 2 rail that attaches to the bbl nut that just has a top rail and smooth mostly everywhere else. The gun is a Bushy lightweight carbine and I am looking at a rifle length rail of at least 12" and possibly 15" so just a pinch of bbl and flash hider are exposed. Main question is are there any downside to the way these rails attach compared to more expensive rails? I don't know any other methods. The next question is what is the downside to cutting FSB other than not being able to use in the future. I figure it would be the best bet for function of the gas system. I also figure the bayonet lug will have to go, no problem with that. This gun is mainly a plinker and predator rifle. I have gone through and staked everything and it has a H buffer in it. I may order a BCG with the rail as a backup but the gun sees no real use at the moment.
lethal dose
10-25-12, 12:34
If you go FF, cut the FSB, spray it, attach your HG. DD and LaRue rails attach better, but the evo, Troy, etc. are fine.

He means he may order a BCG in addition to the HG.
wahoo95
10-25-12, 13:01
I've never seen any downsides to cutting down the FSB. Just shaved this one down yesterday to go under a Troy TRX in a S&W M&P Sport ......of which I learned S&W installs their taper pins from the opposite side as most everyone else. I prefer to paint them with Hi Temp Engine paint.

http://i210.photobucket.com/albums/bb244/a996hawk/photobucket-3957-1351187918744.jpg
Suicycle
10-25-12, 13:29
thanks for the advice
SpankMonkey
10-25-12, 17:28
I've never seen any downsides to cutting down the FSB. Just shaved this one down yesterday to go under a Troy TRX in a S&W M&P Sport ......of which I learned S&W installs their taper pins from the opposite side as most everyone else. I prefer to paint them with Hi Temp Engine paint.

http://i210.photobucket.com/albums/bb244/a996hawk/photobucket-3957-1351187918744.jpg

Wahoo does Smith park under the FSB? I'm thinking about buying a Sport as a cheap training rifle.
wahoo95
10-25-12, 17:41
Yes, they do park under the FSB.
Dlo250
10-25-12, 20:39
13953

I cut my gas block down with it still attached to the barrel. Used a hacksaw and a dremel. Didn't want to hammer it out. I'm not worried about covering it up with a rail the way I would be if I had a set screw gas block. Those pinned on blocks are going nowhere. 13954
panzerr
10-26-12, 08:06
Be advised that you have to shave off quite a bit to fit under a Larue rail. But don't worry, it will still be plenty strong.
Suicycle
10-26-12, 15:31
I generally love Larue stuff but haven't found a rail from them that I like. DD makes a modular rail that I may be in the market for. Thanks for the info on how they attach, I am not sure as to what I am looking at except for the similar ones I mentioned.
ScottsBad
10-30-12, 02:08
Hi,

I prefer the tube type forends where I can add the rails I need. I have a Noveske NSR, a Daniel Defense MFR, an APEX Machining Company forearm, and a old VTAC Extreme on some of my rifles.

I've done the full rail thing, but I NEVER use anywhere near all the rail space, so why hold a cheese grater in your hand or cover rails with panels? If you must have full rails, I like the QUALITY of the Daniel Defence Lite, been around a long time, but is really one of the best IMHO.

My favorite tube type is the Noveske NSR forend (SUPER LIGHT and strong) and has a really nice attachment scheme. Then I like the APEX, and followed very closely by the Daniel Defense MFR. The APEX is a little heavier, but I really like it and their customer service is SUPERB.

The 3 times I shaved the "A" style sight into a gas block were all sucessful. DO remove the gas block before trying to cut it down.
Put it in a vice cut it down with whatever tool you have. I use a pneumatic grinder with a 3 inch cutting wheel, which offers more control than an big angle grinder. I use some other bits to grind it down the way I like it.

What really works nice to coat the gas block is touch up bluing. I have had good luck with Formula 44/40 Instant Gun Blue. Just follow the directions and you can put a nice dark finish on the gas block and no worry about peeling paint. Takes five minutes.

Pounding the pins out is a pain. I remove the barrel. Then I use a punch that has a cupped end on it so it will stay over the pin. I made a block out of 3/4 inch ply wood (Maybe 5x5 inches) with cutouts for the curve of the gas block rings and barrel (Did it with a ball shaped cutting bit). Also drilled holes for the pins. I wrap the rest of the barrel in cloth and tape, lay it on the concrete floor in the block I made. I heat the gas block/sight with a torch (not too hot), and quickly pound the pins out. Its hard to do on the bench because most benches give just enough to make it hard to punch out the pins, the concrete floor has no give.

Install in reverse; Freeze the pins, heat the gas block drop in the pins and pound em in pretty hard.

Good luck and enjoy the ride.