There is the possibility that you have a bad barrel. Also inspect the muzzle for damage and Use a Q-tip in the muzzle to check for burrs.
Sometimes trying to run your bullets too fast can effect accuracy in a bad way.
I too have had better luck with 77grainers in the 1 in 8. VV N540 Re 15.
I have an old Bushy 1 in 9 that shoots the 69s very well with Varget and H 4895.
I didn't say it was your fault, I said I was blaming you.