Hmm...well FAL was dropped for the Galil, Galil was dropped for the M16/M4, and now the M16/M4 is being phased out for the Tavor.
It seems like each weapon is successively lighter and/or more compact. Even the 20 inch M16 is 1 lbs lighter than a Galil.
A Tavor with an 18 inch barrel is the same length as an M4 with a 14 inch barrel.
http://www.israel-weapon.com/default...4e1e40d0422%7D