what they are saying is that the actual bullet diameter of a ".223 Remington" is in fact .224 inches, as is a 22-250, .222, and .220 swift. Despite the name ".223" the bullet in a ".223 Remington" is not actually .223 inches in diameter... and so the answer to your question depends on whether you mean the bullet used in a ".223 Remington" round, or a bullet with an actual diameter of .223 inches. If you mean the bullet used in a .223 Remington (.224 diameter), then yes you can load it in a .22-250 cartridge, if you mean a bullet with an actual diameter of .223 inches, then no, it may wobble as it travels the length of the barrel.... and if there's any chance you mean (and I don't really think you do, but just to clarify) using a round of .223 Remington ammo in a rifle chambered for .22-250, then definitely not