BCM gas block and Centurion CMR rail- shave it?

[jackblack73]

I recently installed a BCM ELW barrel and gas block with a Centurion CMR rail. As you can see, the bottom of the gas block is pretty much up against the rail. I was planning to just grind down the bottom of the gas block for a bit more clearance. Any downsides to doing this? There's plenty of room to remove material before I reach the screw heads. I've shaved a couple FSBs before, so this should be easy. And I'm not planning on any builds for a long while, so buying a different gas block just seems like a waste. Just wondering if I'm missing anything before I do it.

http://i36.photobucket.com/albums/e5/jackblack73/AR-15/BCM%20gas%20block.jpg (http://s36.photobucket.com/user/jackblack73/media/AR-15/BCM%20gas%20block.jpg.html)

[GH41]

That's a known problem with the original CMR rail. If I remember correctly the BCM gas blocks are on the list of what won't work. As cheap as gas blocks are I would ask Centurion what they recommend. With a whippy barrel you need all the clearance you can get. I wouldn't feel comfortable with less than a tenth. You are probably going to have to use a pin on instead of a set screw block.

[Rifleman_04]

Just get the centurion gas block.

[jackblack73]

As far as I can tell the Centurion is only available in 0.750. The ELW is 0.625.

[Clint]

The best thing to use is a purpose designed .625 gas block with smaller outside dimensions.

This should clear the rail without grinding.

[Iraqgunz]

I think mine has the Sadlak block and it works fine.

[Wolfpack45]

Just shave and refinish the exposed metal.