If you use the GemTech Bi-Lock flash suppressor.
Bi-Locks can be had for many different weapons on special request from Gem-Tech.
I might recommend they (or a very competent smith) do the installation.
Most of the suppressor manufacturers offer some type of system for using a suppressor with
a flash suppressor. Just have to use their proprietary model flash-suppressor.
Gem-tech - bi lock, or the HALO which mounts to 22 mm standard NATO-specification bird-cage type flash hider
Smith enterprises - vortex (this should be offered by more mfgs IMHO)
AAC - M4-2000 flash-suppressor (not sure exact name )
SWR - SpecWar2 mounts onto std A2 style flash hider
And I'm sure there are a host of others... these are what I am familiar with
However most of these systems are for use on 5.56 series weapons (AR, Sig 552, G36, etc...)
options are more limited when going to 308.
BTW - maybe we move this thread to the class 3 forum.... anyone ?