Reply #11: No...

[shaayecanaan]

the only ballistic missile that Israel had at the time was the Jericho I. The Jericho II was not introduced until the late 80s.

Jericho 1 weighed 6 tonnes and carried a payload of 400kg, although admittedly its throw-weight was probably less than half of that. Regardless, reducing that payload to 200 kg (say) would only reduce the weight of the missile by about 3%, and maybe its effective weight by 6%.

Even then, that might not necessarily increase range as it is the overall ballistic performance of the missile that determines range, not the weight, and the missile is more or less designed to carry a payload of 400kg. Putting helium in a football instead of air reduces its weight, but doesn't mean you can kick it any further.