Re: 69 gr. SMK HPBT need load!
How old is your rifle? Some of the older PSS 223 rifles had really long lead/freebore, I've also read where some of the newer PSS 223 rifles have more reasonable lead/freebore.
What is an OAL for a 69 SMK to touch lands in your rifle?
Have or will you modify internal box magazine so you can load out longer than what Rem shipped you? Pros & cons, 69 jumps well but you can pick up some performance (more case capacity, less bullet jump) by seating out to jump 0.020" or so.
Benchmark, H4895, Varget, N-140, RL-15 would all be valid choices for a PSS depending on lead/freebore dimensions for YOUR rifle.