With it's .473" standard size rim diameter and normal pressure in the 63,000PSI range, stay away from the Swift. It's for strong singles like Ruger#1's and bolts only.
: The .22HiPower also has the big rim, but lower pressure is normal, being originally built and loaded in early M99 lever guns.
: I think a .218Bee, sort of a modern rook rifle would do the gun justice. At around 40,000PSI to 44,000PSI you can get up to 3,000fps with 40gr. bullets, with limited breech thrust from the little ctg. The Hornet is another, slightly smaller capacity round that requires a carefully designed reamer. Standard, sloppy old style reamers in hornet don't produce accurate guns. Modern brass is undersize compared to brass of the 1950's where most reamer specs come from. Thus, bases are way oversize, etc. There is also a big difference in brass from different mfgr's.
: Since you're from Sweden, you'll likely use Norma brass - good stuff, but I have no experience with it. I think it is slightly larger than typical US made brass.
: Whatever ctg. you decide on, buy the brass, measure it then order the chambering reamer .001" larger in the head/base, .001" larger at the shoulder, and .0025" larger on the neck than a loaded round's neck diameter. If you leave those specs to the reamer maker, or some gunsmith with some old reamers, you'll probably suffer from sub-standard performance as they'll use the old standards - large and sloppy. Your cases will stretch, keep stretching no matter how you load and fail early.
; I've always liked my Hornets in the CZ's and the older BRNO, however only the CZ's are accurate and they'll shoot as well or better than anyone's .222, .223 or whatever. They have proper sized chambers, much smaller than typical 'old/school' Hornet chambers - CZ knows how to make an accurate Hornet - most other outfits don't. It's all in chamber specs made to match the brass. No stretching and very long case life with 3,300fps+ loads (bolt)(3,000fps in your double) Properly chambered, the brass doesn't even lengthen, which all the oldtime 'gun writers' tell us is the result of the tapered case - bull!