Am relying on measured velocities from chronograph, in conjunction with current published manuals, while taking into account the specific bullet, brass and primer.

By the time you get primer flow, flattened/pierced/blown primers etc, ya are likely loading too hot already.

Imo, handloading towards the upper end without a chronograph is ill advised. A Beta F1 master is cheap assurance.

Certainly others may have different opinions.