I've shot and used both.............
When I loaded the Swift down for real serious accuracy...It's was runnin bout the same as the .22-250.
My all time favorite of the two, is the .22-250 load with a Sierra 52 gr HPBT Match bullet.
But, I've just about started using the .257 Roberts for an every day kinda thing...Bucks the wind a bit better over distance.
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