More like fast twist 22-250. And Creedmoor is on a whole different level. I think with lighter bullets there are diminishing returns with 22 Creedmood (compared to 22 ARC).
Before the previous post, I took a look at Hornady ammunition (to compare apples to apples).
- 22 ARC, 80gr ELD-X, 3010fps
- 22 Creedmoor, 80gr ELD-X, 3285fps
Both of those were Precision Hunter series. Compare that to:
- 223 Rem, 55gr V-Max, 3240fps
- 22-250 Rem, 55gr V-Max, 3680fps
Those both were Varmint Express. You cannot do direct comparison between all 4, using factory data, since they're catered for different use (no common bullet or even weight).
You can, however, compare 75gr in both 223 and 22 ARC and draw some conclusions between 22 ARC and 22-250 from there. These both are Hornady Black product line:
- 223 Rem, 75gr BTHP, 2790fps
- 22 ARC, 75gr ELD-M, 3075fps
So 55gr is 8.4% slower from 223 than 22-250. And 75gr is 9.3% slower from 223 than 22 ARC. It's reasonable to consider 22-250 and 22 ARC somewhat equivalent but different approach.