Not that I’m an expert but going by what I’ve read over the last 20 years and what I’ve experienced, any modern can rated for 5.56 should handle the Valkyrie. Slightly heavier bullet, same diameter and about the same velocity SHOULD equate to about the same impact(figuratively) on a 5.56 can.
As far as the bullet diameter, yes. "223" and "Five-Five-Six" bullets all measure between 0.2238" and 0.2245" on the bearing surfaces. The can's bore is probably 0.275-0.300" or better...being a Surefire.
But I wouldn't do so until I called Surefire and asked them if they felt comfortable with the Valkyrie, and if so, at what barrel length minimum.
It's the PRESSURE rating that is key here, not the boolit.