[Rupert]

The G3 series could be taken apart by pushing out a few pins, like the M16 family. You'd then have the stock and recoil spring, say 50cm long roughly, the trigger group, and the barrel and receiver group about the same length as an M16's upper group (the G3 had a longer receiver but a shorter barrel).

Also, the G3 had a removable scope mounting that was designed so that it wouldn't change its zero if removed and replaced. I remember reading a review of the weapon and mount where the reviewer tested this and found the point of aim moved no more than 1" at 100 yards (about 1MOA), which is more than good enough for a battle rifle.

The biggest drawback of a G3 as a take-down weapon is probably that it's made from a lot of heavy gauge steel stampings and is thus quite heavy (HT says 11.4/1.7 pounds, and you'd added another 1.5 lbs or so for scope and mount).