The 220 Swift has been around for 85 years there is a reason for that, "it works" I have never seen until recently swift brass or ammo not be available "in all fairness nothing is available" it is one the calibers I have been shooting for the longest time.
they only thing better than a 220 swift is they ackley improved version of it. I have several I know you want to shoot heavier bullets than I do, but a 220 swift AI will send a 40gr Vmax over 5000 fps all day long that translates to almost 500 yards with
minimal bullet drop those numbers are hard to ignore. So I don't think a 220 swift will have any trouble handling those 55gr
or what ever you decide to load, speaking of 55gr they are good for 4000 fps easy.
Dean