You keep throwing out pressure. Doesn't the 5mm Remington Mag have a max pressure of 39,000 CUP? That would seem to indicate pressure is not the issue in rimfire cartridges you seem to think it is. That is 22 Hornet level.
Yes, and in the original rendition of the ammo, it had a lot of problems, resulting in extractor problems, etc. The Centurion ammo is using a lighter bullet and different powder to get where it needs to go, at easier-to-handle pressures.
The technology today MIGHT make it easier to get something worthwhile here, but we won't know that until there are a few out there getting used.
We can speculate all we like, but we won't know a thing until it gets here and some knowledgeable people get to try it out.
