I am getting ready to build my first ar.  I want a 16" barrel but want to conceal the gas block under a full length handgaurd.  I was wondering if this posed any potential problems (for a newbie assembler) or if it required anything special such as a smaller gas block or a two piece handguard?

Thanks

Rob

Most floating handguards are designed / manufactured of such a length to terminate just behind the "stock", full height front site post allowing use of the front site.  However there are several solutions to what you want to do.  Obviously, if you want to cover the gas block with the H.G. then a cut-down front sight post or dedicated gas block will need to be used.  These are available from a variety of sources such as Metalcraft, Les Baer, JP Enterprises, and others.  Most are secured to the barrel using setscrews rather than the original taper pins.  When you cover the gas block with the H.G. then the easiest solution is to use a 2-piece H.G. where the barrel nut secures the barrel to the receiver, the gas block and gas tube are installed, then the handguard is screwed onto the barrel nut thereby covering the block.  Your choices of handguards long enough to cover the block make your desired outcome a bit more difficult.  You can use a 20" H.G. left full length, but it looks kinda dumb since the H.G. will extend almost all the way to the end of the 16" barrel.  Another option is cut a 20" H.G. down to your desired length.  Two-piece H.G's subject to cut-down are made by a variety of manufacturers.  Another option is to use a one-piece H.G. with very small holes drilled from the bottom for access to the gas block setscrews after tightening the handguard into place and slipping the tube/block assembly into place.  You still need to cut a 20" H.G. tube back to your desired length.  Hyperform Inc. makes custom length carbon fiber 1-piece tubes cut to your desired length, but setscrew access holes will need to be drilled after H.G. installation.  I know of no other manufacturers that make custom length tubes that will cover the gas block.  Good luck.

Get a "Dissipator" from model 1 or Bushmaster or J&T.

Full length sight radius and handgaurds on a 16 incher.

It's very easy to do. I just cut down my existing gas block and installed an Armalite NM fiberglass handguard. I'm pretty sure most handguards would clear.

I like the look of it and it gives me more hand room. Plus you can quickly remove the handguard and clean under there. On a 16" barrel about 3.5" sticks out

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