one thing concerns me about your choice and thats quotes like this one
"Traditionalists have roundly condemned it as an overbore "barrel burner" which can wear out a chromoly barrel in as few as 200–300 rounds, especially if long strings of shots are fired from an increasingly hot barrel"
maybe the swift is one cartridge that belongs in this thread
viewtopic.php?f=12&t=1854 LOL
why not look for an older sako chambered in 6BR, they're a slow twist to suit light varmint bullets or even a 6PPC,
a .220 swift will push a 35gr bullet at around 4400fps
a .204 ruger will push a a 34rg bullet at around 4200fps but has a better BC so will shoot flatter
a .22BR would push a 40gr bullet at 3900fps, should outlast both the swift and .204 ruger by a factor of 2X
a .220 swift will push a 60gr bullet at around 3600fps
a .223 will push a 60gr bullet at 3100fps but will outlast the swift by a factor of 5X (assuming the correct twist barrel is used)
a .22BR will launch a 60gr bullet
a .243 will push a 60gr bullet at 3700fps and should outlast the swift by a factor of 2X
a 6BR pushing a 60gr at around 3600fps (assuming a slow twist barrel is used)
there are many options, but you should consider all the factors
Chronos