gas block picatiny rail

[fr3db3ar]

Why would DPMS make the front rail lower than the mail rail?  I just bought some railed handguards that are carbine length and not free floating......just to replace the glaciers and allow a bipod.

They run on the same level as the main scope rail and it pointed out immediately that the gas block rail is lower.

??

[98Z5V]

Several Manufacturers do this, and there are specific front sights that are of the proper height to attach to a pic-rail gas block.

The Armalite pic-rail gas blocks are some of the finest I've handled - they're good.  <thumbsup>

[Robocop1051]

DPMS, PRI, JD & MI (wow, we like acronyms) all make rail height gas blocks. Personally, I think PRI & JD make the better looking blocks.

[98Z5V]

^^^ Like Robo pointed out...  Those guys he listed make gas blocks that will line up with the rail height.  No special-height front sights necessary (but do not use a MagPul polymer sight on any gas block attachment...). 

The initial, early gas blocks with Pic rails were lower, and do require a special-height front sight.  Definitely something that you have to pay attention to when you're shopping for front sights.  "Standard" would be a good product description for a sight to mount on a free float rail, or one of the gas blocks that Robo mentioned.  Front sights for a lower-than-rail-height gas blocks will definitely have that in their product description. 

Here's an example, from Midwest Industries:

http://www.midwestindustriesinc.com/index.cfm?fuseaction=category.display&category_id=79