This has probably been done before, but I thought I'd share some stock weight data. All stocks weighed with full hardware attached using a USPS digital scale.

std=standard; BR=Big Red; FG=Fiberglass;

SAI plastic 2lb 5oz
GI walnut BR 2lb 12oz
SAI walnut 2lb 8oz
GI birch std #1 2lb 12oz
GI birch std #2 2lb 12oz
GI birch BR #1 3lb 1oz
GI birch BR #2 2lb 14oz
GI FG #1 2lb 14oz
GI FG #2 3lb 3oz
GI FG #3 3lb 1oz
McMillian M1A 3lb 14oz
Vltor EMOD ?
Sage EBR Mod 1 4lbs 14oz
SAge EBR Mod 0 5lb 1oz
JAE gen 1 w/o side rails 5lb 6oz
JAE gen 1 w/side rails and adj cheek 6lb 1oz