I have this
here is the rail
https://www.rainierarms.com/rainier-arms-switch-308-rail-14
and the wrenches
http://www.amazon.com/PRI-Dpms-Barrel-Torq-Wrench/dp/B00JF79XPC?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
and
http://www.gem-state-armory.com/ar-armorers-wrench/

And nothing works to tighten the barrel nut, I am out of options.

Most 2 prong barrel nut wrenches will work.  If you can find them, this one too.

One more question, Are your 308 barrels bulled out in the area where the barrel nut is? I have been having issues for weeks trying to get a rifle together because of the barrel and/or the barrel nut. and I am about to throw in the towel and sell it and just buy a built rifle.

Our barrels are contoured where they fit a standard .308 barrel nut.