I prefer using the mass driver from our secret lunar base...
Niffty idea BTW. Why tungsten when concrete is so much cheaper?
Doesn’t have to be tungsten but I was also thinking of what is happening to the steel casing of heavy wall drill stand if its on a re-entry and facing extreme temperatures.
Might be better if they had a 1” thick ablative silica sleeve identical to the space shuttle tiles. Like a protective blanket and some stabilizing fins these orbital darts so to speak will be impacting at lets figuratively say Mach 6.
With a dense inner core of a tough super hard metal this would and should act the same as a Abrams penetration munitions round. Except it will burrow deep shedding its outer casing and the inner dart will punch through any concrete and “spall” shedding high speed plasma style particulates that will burn through anything.
Of course the experts building munitions have a better handle on all this and I’m sure this is an old concept.