The A3 on my FN SPR weighs right at 3lbs. That is with a heavy barrel channel and inlet for the FN DBM. Maybe a few oz more with a smaller barrel and standard floor plate inlet.
Josh and all: None of our stocks have a fixed "weight" that we quote. The finished weight depends on the caliber requirements, the inlet, the options you order on it and the length of pull. An A-3 could vary from 2.75 to 4+ pounds.