they are screw in. I put in a brass sleeve and tapped it for the threads with mixed results. a couple of them are still held in with glue. The others he could swap out for a broadhead in theory. I tried to make a jig to drill the hole centered, but it only worked so so. I may have to settle for glue on tips, but I would really like a way to make field points for shoot shafts. I have a good system for bamboo, but it involves about 3 inches of threaded rod. Hard to drill straight 3 inches into a shoot. What do the rest of you do?
BTW, my brother asked how many hours I had into the bow and arrows, and I told him he didn't want to know. I lost count a long time ago. But this stuff is maybe more fun to give away than it is to keep.