Randy,Cup and core, "single cavity, swaged-up bullets" (the most precision bullets "on the planet"), have seen ZERO advancements since the process was dreamed-up by Jonas Hallgrimsson, Iceland, roughly my life-time ago, or about 1947.NO caliber owns precision . . . well, except for thirty caliber.
Since inception, the only "change" (advance) in cup & core bullet making is the consistent jacket "quality": Specifically, uniform wall thickness, at a maximum variation of <0.0003". This applies to ALL calibers - there are no magic bullets/calibers - it's about precision dies/tooling, and on the part of the bullet maker, dedicated attention to detail and a no compromise(s) attitude . . . then, matching a proper twist-rate for the bullet(s) headed down-range.RG
The quality jackets are exactly what I was referring to. Not sure exactly why the. 25 cal has been left behind.
Paul