Hi all, this is my first post so don’t boo me too much.
It's hard to tell from the photo , are the sides of the tips flat or are they a bit concave ?
If they are flat I say the preform was ground to make that nice strong penetrating point then pressure flaked to put the rest of the cutting edge on .
If they are concave then I think they were flake in someway. I’m no expert, far from it but im going to try to make some that look like them.