From My experience in the Canadian Army Reserve, we were taught to attack the head neck or up and under Any body armour or the arteries in the Legs....
That spring technique works only if the kerf on the inside is wide enough that the plug work catch. If you are drilling into wood with resin or sap,...
I haven't taken the time to look for it but a couple years or more ago there was a thread with a helix swimming upstream in a creek or river. someone...