One of the problems with the 223WSSM it need a chrome lined barrel. If you look at the loading data for the 223WSSM it's using 45gr of powder and has H20 capacity of 53gr. You could build a 22-250AI use less powder(5gr-7gr) maybe be 100fps less and 200fps less with the 22-250 using (5gr-8gr) less powder.
Same thing with the 243WSSM/243 both have the appr same capacity H20 54gr and if you look at the Nolser data the 243WSM has appr 100fps advantage but the 243WSSM has a higher PSI spec 65K vs 60K for the 243.
Plus/Minus with everythng