Pinned Gas Block Service
Your new barrel is avalible with a pinned on LaRue gas block. The gas block is installed with green loc-tite, the set screws are set into detents in the barrel and tightened with red loc-tite, then a taper pin is installed with green loc-tite with appx .040" barrel engagement. This does not deform the bore. Dont even think about taking it off. The green loc-tited gas block and red loc-tited screws in detents are more than enough. The pin is not necessary, but if you still want it, here it is.
this is a quote from Noveske's.....you decide...the pics on the site dont have any staked screws
http://www.jnrifleworks.com/cgi-bin/cart2/display.cgi?cat1=8
http://ken-co.com/permatex/threadlocker-green.pdf#search='green%20loctite%20290%20temperature'
however...from what Ive been reading....green loctite really isnt has permanent as people think.
it seems that loctite 272 is stronger and will take higher temps.
http://loctite.com/int_henkel/loctite_us/binarydata/pdf/lt3770_Threadlockers.pdf
look at the chart at the bottom.