I have had these arrows for two years but they have not been shot at all until this Feburary. I was shooting them in my old hoyt at about 210 fps. I maybe shot them 80 to 100 times. I have been checking them closely for vane clearance and they were in great shape.
I have shot my new bow shooting about 276 fps for the last two days maybe 30 - 40 times each night. Tonight about half way thru I noticed about a 1" long crack back by the nock on one arrow. I checked all the others and they looked good. After a few more shots another one cracked. I checked the nocks they are not overtight I can still rotate them, they are not loose enogh to come out but loose enough I can still rotate them.

Anyone know whats going on?

They are 5575 Gold Tip XTs cut to 261/4" according to the spine chart I am OK. See my Signature for bow specs.