More experimenting. Only 1 day left of the Multisim trial so I better make good use of it. So… It turns out a couple of those resistors arent necessary, simplifying the circuit. It still works perfectly fine. Short out R5 and the load goes to 450mA, never more.
If the physical circuit works just as fine as in the simultor, this could be quite a nice, cheap circuit to protect me when Im experimenting and hooking up jumper wires all in a mess on a breadboard. Ya never know when the next short circuit will happen.