[giantmike]

FYI, Winchester has introduced another straight wall cartridge, the .450 Legend, suited for AR-15s and other action types. It headspaces on the case mouth. Rim diameter is .422", same as our 6.8 SPC, thus rifles chambered for it will have bolts suited for replacement barrels chambered in 6.8 SPC. Same goes shell holders. So, if you always wanted a bolt action 6.8, the gun world just became a little more accommodating.

The .450 Legend is interesting in its own right, see the SAAMI chart below. While the case rim is .422", it is rebated behind a .440" case head. Note the gradual taper to .427" at the case mouth, the very short .4015" diameter by .010" long throat, behind a 1 degree-30 minute leade down to the barrel's .390" bore. I guess as long as you keep your brass trimmed to just the right length, headspace should not be a problem. Personally, I prefer cartridges that headspace on rims, belts or shoulders, no matter how skimpy. - CW

https://saami.org/wp-content/uploads/2023/01/Public-Introduction-400-Legend-2023-01-30.pdf

Those drawings say 400 legend are there two new cartridges? 400 and 450?