If the bullet itself also enlarges and egages the rifling, them maybe. That said, you would think that the manufacturers of the bullet would be doing some research and visit with states to try and grease the skids for legality.
Their website makes it sound like the copper part of the bullet doesn't engage the rifling. And even if some states outlaw it, they'll still have plenty of others to market it in so I doubt they're worried about that. Just look at how many different sabots are on the market.
I thought I might try these, but at 270 grains, I'm not so sure. I kind of like heavier bullets.
