I bought one of the 20” GII Remington R25 308’s last year. It shoots surprisingly well and is around 7.5lbs with its fluted SS barrel. Their blueprint is not a bad one. Handles like an AR15 and is becoming one of my favorite hunting rifles.
According to Remington, the first gen R25's were heavier:
Type: gas-operated, semi-auto
Caliber: .243 Win.; 7mm-08 Rem.; .308 Win.
Barrel: 20"; free-floated; 1:10" twist
Trigger: single-stage; 4 lbs., 2 ozs. pull
Magazine: 4-round detachable (accepts some other AR-10-style mags.)
Sights: none; Picatinny rail for optics
Safety: two-position
Stock: Zytel; LOP-14.125"
Overall Length: 39.75"
Weight: 8.75 lbs.
MSRP: $1,567
So if you compare your rifle to the GI, the OP can get some hints on getting the weight down to what your rifle weighs. The stock is lighter, the GII also uses a lighter BCG, so if wanting to build a lightweight AR10 6.5 creed, he's going to have to start off with a lightweight barrel and go from there with lighter parts. Maybe he can do some research and see who offers the lightest receivers. The AR10's are all over the board when it comes to receiver heft. I know my new S&W M&P 10 weighs 9 pounds from the factory and it has a pretty slim barrel on it.
The OP wants a 7.5 pound rifle, he's going to really have to work hard to scrape that together. Probably going to have to be more selective on the parts he does buy...
