Atlantic Marksmen brand ammunition has been previously mentioned by DK in his thread on Polycase (http://iaaforum.org/forum3/viewtopic.php?f=8&t=15909&hilit=Atlantic+marksmen)
I recently had a chance to discuss Atlantic Marksmen with one of their principles. They are a company who advertises Euro-American Elite Ammunition manufactured using components with produced by their partner companies Lapua (cases) and PolyCase (bullets).
They are in the process of setting up their loading facility in Gulfport MS and establishing their distribution network, but in the interim their first production ammunition (9mm Luger) has been loaded by PolyCase in Savanna Georgia. This includes PolyCase Firefly tracer bullets and Polycase ARX personal defense bullets, both loaded in Lapua cases. These items will likely first be offered on the retail website http://buygunsandammo.com/ beginning by the end of next week. It is possible they will also offer the PolyCase RNP load, but this will not be part of the initial offering.
Atlantic Marksmen recently completed a series of tests with their ammunition, including the FBI Barrier Tests. I hope to have those test results in the next week.
It sounds like Atlantic Marksmen may offer other calibers in the future but no specific information at this time.