from 200mg of pure K will get me k-holing... i used to have a pretty insane tolerance.. it mainly depends on your tolerance.. i had a pretty insane tolerance at one point, but now i only go "explorin" very rarely so i need less...
acording to erowid the insufflated K-hole dose is 1mg/lb, oral and rectal doses are 3 to 4mg/lb, and the IM dose is 0.75mg/lb
erowid doesn't mention IV but the K-hole dose is very low, and you should be sitting down, cause people report starting to k-hole when they still haven't emptied their rig... in fact its very dangerous, not many engage in this ROA