I was looking through a loading manual the other day, and then at the Green Mountain sale on .223 barrels for $30.
Hmm... I've mostly been a big-bore fan, but the .22-250 looks like a sweeeet cartridge. Many of the loads I found exceeded the velocity of the .220 Swift with the same bullets.
Downside: the 4000+ fps loads were all around 60,000 PSI. Some were listed at 3100 fps and 39,000 PSI, which is quite respectable. SAAMI max appears to be 65,000 PSI. Yawp! 7.61x51 SAAMI max is 62,000 PSI... I couldn't find any pressure specs for commercial ammo, but I don't think I'd be comfortable shooting anything that hot with an AK action.
For handloads, looking through a couple of different books showed that the .22-250 is quite flexible as far as loading components, and still delivers good velocity even at substantially lower pressures.
Hmm... you know, if you short-chambered the barrel by .030" or so and adjusted the dies appropriately for your reloads, you could ensure that the bolt would not close over a commercial .22-250 cartridge. I guess you could call it a "semi-wildcat."
Hmm... sure would be a lot cheaper than the 6.5mm barrel I want for the Hadar build... the difference in length would require the use of a .308 mag, at which point the .300 Savage starts looking good again.