No, it shoots 45LC, 454, and 3" 410. I guess they had problems with the 28 gauge prototype at the SHOT show with BATF and pulled it. Word is it will not be put into production now.
Picked up the RJ a few days ago... it makes a Ruger Alaskan look like an ankle gun. This thing is massive and heavy. I think a shoulder rig will be the only carry option.