Lighter fletching (smaller, feathers, etc). Ditch the wrap if you have them. Or, if the inserts were installed with superglue you can screw in a field point and CAREFULLY heat it with a torch then pull the whole thing out. I've done this more than a few times with test arrows, ruined a full carbon shaft cuz I got it too hot, but it is possible. Carbon acts like a heat sink so once it gets hot it stays that way for longer, it doesn't cool quickly enough so repeated heatings just get it hotter until cracks form. The key, I found, was to heat the field point enough to get the insert to twist then I kept twisting it until it came out. Again, I've only done this to test arrows and I'm not sure how detrimental it would be to hunting shafts that be subject to impact on a shoulder or rib. Might be worth a shot though on an FMJ.