What's it's weight on a baby scale, now ?
If it already weighs only 7lbs, there's no way 2 lbs can be shaved off it - the only 5lb CF BA factory rifles I'm aware of is a NULA. or a Weatherby UltraLite (in standard cals), but LW customs can be had from Rifles, Inc or Christiansen Arms.
FWIW, Weaver 2-piece bases are about the lightest around, and even WallyWorld sells alloy rings to fit them.
"Some" BA rifles can be run w/o the sheet metal magazine well liner (not very heavy, but still weighing something )- unless your rifle has a detachable mag (you haven't given a complete description, as yet).
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