Are you putting a footing on the nock end as well? I've been footing the front end for quite a few years but I have a bunch of arrows that split at the nock end on hard hits.1000%
I've broken a dozen nocks and never hurt the shaft.
Chuck up on a big rock.....THWACK!
nock splits and flies to infinity and beyond.
Stuff a new nock on and rock on.