I’ve found that between 140-150pf is the sweet spot with 124gr jacketed bullets in my setups. Both my rifles have 14.5” barrels with blitzkrieg buffers, 308 rifle springs and weighted spacers between the bolt and buffer. This has proven to be the optimal setup for me in terms of reliability and dot movement.
i tried short stroking my buffer system with a spacer in the bottom of the tube, but with direct contact between the bolt and buffer I was destroying blitzkriegs. Since I put the spacer between the bolt and buffer I have really tamed down the recoil of the rifle and (I hope) solved the problem of broken buffers.