Originally Posted by
BruceB
The rifle was NOT "designed for" any particular cartridge.
The factory takes a STANDARD action, and screws-on a STANDARD .22-caliber barrel, and chambers it with a STANDARD reamer for the cartridge involved. The only "design" component is the marketing sector trying to "design" a package that will sell on the market.
The actions ARE designed (and over-engineered) to contain pressure variations FAR higher than the piddling differences between the various .223/5.56 loadings.