What state are you in? I can do a simple barrel change and cut it with an M852 chamber which is specifically designed to use a 168 grain SMK or I can use a M118LR modified chamber which was designed for the 175 grain SMK and is specifically intended for the precision 308 handloader.
For general purpose but use with occasional match ammo, I recommend using a M852 chamber headspaced at 1.634" which is not too loose for accuracy work and not too harsh on the handloader's brass, yet still not too tight for someone who wants to shoot
GOOD quality 7.62 NATO surplus ammo, like Federal white box XM80. This is on the long end of the spec for a new 308 headspace chamber, but just short of 7.62 NATO minimum headspace (which starts at 1.6355"). The M852 chamber also shortens the bullet jump for the shorter bullets like the 125's and the 150's, where the M118LR lengthens the bullet jump to accommodate the 175 grain SMK.
I can cut it with a M852 chamber but headspace it for 7.62 NATO (1.635") but I don't recommend the 7.62 NATO chamber unless you're just going to shoot surplus 7.62 NATO ammo and expect 5 MOA groups. The 7.62 NATO chamber is very loose and made to reliably function with various ammunition makers from different countries with different levels of QC.
Tony.
Owner, TonyBen, LLC, Type-07 FFL
www.tonybenm14.com (Site under construction).
e-mail: tonyben@tonybenm14.com