My Stag 10 is at 6.51lb bare, 7.81lb with optic & mount, 8.3lb with sling & bipod. I'm into the rifle for about $5500 total.
I'm using the Brownells Titanium BCG, it is actually a few grams lighter than the V7 Weapon System Titanium BCG. So far it has run fine for 200 rounds.
Here's a quick run down on parts
Lower:
MFT minimalist stock
V7 weapon systems lightweight buffer tube
V7 aluminum castle nut & aluminum endplate
JP Enterprises Silent Capture Spring System
Radian Ambi Safety
Hiperfire Eclipse trigger (probably will switch to a Geissele, will save 20grams)
V7 light weight magazine catch
V7 .308 Titanium takedown pins
Brigand Arms Carbonfiber grip (just run a magpul K-grip they are the same weight)
V7 titanium grip screw
Upper:
MRA 18.6" pencil barrel, .308win
V7 thread protector
SLR titanium clamp on adjustable gas block
brownells black rifle length gas tube
V7 Weapon system 15" hyperlite handguard
Brownells Titanium BCG
POF roller cam pin
Magpul M-Lok QD sling adapter
Magpul 2" rail section for bipod
Aero Precision ultra light scope mount
Vortex Razor HD LH (light hunter) 3-15x42 scope
Accessories:
Neopod bi-pod (these are awesome, be prepared for sticker shock)
Ferro Concepts Slingster.
If you are concerned about weight the bigger more expensive items have the best value for saving weight. Barrel, Handguard, BCG, Optic, optic mount, buttstock. All the little titanium parts don't add up to much and are expensive