In Gurps, how powerful do you need to fight a tank?

[Anthony]

Originally Posted by sir_pudding

The T-72 is a 54 year old tank, but yes typo.

Note that this still more than DR 60, though and will stop .50 BMG AP.

.50BMG AP is officially 13d+1(2), so needs about DR 90. That's probably overestimating its actual performance, but it's the 'official' value.