Urbanrifleman -
Howdy !
From what I've read, the 22XC will have more case capacity than the stock .22-250. Perhaps enough to drive you to use of a powder w/ a " burn rate " slightly slower than what you used in .22-250 ?
My wildcat .22-35 Remington has case capacity similar to that of a notional " .22XC " . While I myself used to shoot IMR4064 under Hornady 55SX in .22-250's w/ 24" 1-14 barrels, I much prefered WW760 under the 55SX when shooting .22-35Remington in a 24" SS 5-groove 1-14 Hart.
I have gravitated over to use of FED Large Magnum Rifle Match primers along w/ powders like WW760 and those even slower in " burn rate ", as they seem to work really well w/ powders in this " burn rate " range
I like to shoot high load density, but by way of example.... would not be able to shoot a completely full
( .22-35 Remington case ) if I were to use 6.5 StaBal or Hybrid 100V as obtained pressures would be too
high.
Do also like the idea of using temperature-stable powders. Were I to try another 24" 1-14 .22-35Remington, I would try some H4831/SC or perhaps IMR4955 to see how good accuracy is, along w/ checking for useful vel; and safe pressures For my use groundhogs, the 55SX has been my go-to bullet for decades, for ranges of around 435yd and under. I used a prototype of Hornady's 55 "V"-Max for a 510yd groundhog kill.
YRMV
With regards,
357Mag