Mass driver for commodity supplies

I've come across the mass driver launch system several times over the
years. In Marshal Savage's book (collinizing the galaxy in 8 easy
steps), the author proposes building a mass driver in a tunnel up the
side of Mt Kilamanjaro. That mountain is close to the equator and
high enough to get above most of the dense lower atmosphere. The
tunnel would be evacuated and have high speed doors (simular doors
are used in underground nuclear tests). Lasers on top of the
mountain would vaporize ice at the vehicles base to provide the
remaining delta vee to reach orbit.

I beleave that aerodynamic heating and erosion would be signifigant
problems to a mass driver launch system. Spacecraft returning from
space dissapate alot of their energy at extreme altitudes. Running
into 1 atmosphere at orbital velocity would generate tremendous
heat. This may be able to be dealt with, missle warheads have been
able to survive reentry at high velocity for over forty years.

As for the gun launch system, look for info on project harp. In the
1960s, Gerald Bull conducted a number of tests and research using
modified naval artillery guns. There were plans for firing a shot
with rocket motors into orbit before the progect was canceled. In
the late 1980s before his death, he was constructing a supergun for
Iraq.

There is no new technology needed for the gun launch system to work.
They could have done it in the late 1960s. As for the mass driver
launch system, small projectiles have been boosted to very high
velocities, but scaling up to a usable payload may be problematic.