I've got the weight comparisons for std. CAR vs. Expedition vs. LW Tacticals, but I ran off and left them in the truck at the shop. I'll call in the morning and get those for you. I do remember that there was only .05 lb difference between the Expedition and the LW Tactical Kit (the Expedition was the heavier).
Finally I have the info for you. Weight of a standard AR-15 with a 16" HBAR with a crowned muzzle and A-2 stock weighs 7.05 lbs. complete. The 16" expedition weighs 6.85 lbs. and the lightweight tactical weighs 6.80 lbs. These weights are all with A-2 stocks and A-2 uppers.