I have a new 6.8 upper i am building and have had trouble before with tight gas blocks but nothing like this one.  Its the right size .750 and its a Badger speed block.  The barrel is a 16 inch from Dennys,  The block does not want to go on the barrel.   I have had to bump it to get it were it is.  The gas tube is lined up perfect and slide in easy after aligning the barrel nut.  Prior to trying to mount the gas block.   Any suggestions?  Also the gas tube does not want to go the whole way in the gas block either.

Looks like the problem may have been my lack of knowledge in how to fit a gas block.  The last one I had I was able to work it on with out too much trouble.  No way this one was even close.  I have a Larue inbound thanks to Denny.  He is flying it in on his private corporate  jet.  I remember him saying the big guy upstairs was his co-pilot.  No one else would fly with him.

The Larue gas block arrived was installed in about 3 minutes.  Nothing but LaRue gas blocks for me from now on.

+1 for Dennys customer service.