Thanks to the California legislature and our friend Arnold (NOT!), California residents have been prohibited from possessing firearms in the .50BMG caliber unless they submitted their DROS paperwork to CA by December 31, 2004 and register the gun by April 30, 2006. Yeah, does sound a bit redundant being required to register a gun on which there is already a "Dealer Record Of Sale" filed with the state, but that's how they do things out there.
This CA 50 BMG ban applies to the 50 BMG cartridge as defined by precise dimensional specifications. The .50 DTC is a new cartridge made by trimming down a 50BMG case which may then be loaded with the same bullets used in 50BMG rounds and fire formed.
We're already shipping .50 DTC rifles to California (the serial number prefix is "FC-"), and have tested our guns with trimmed and resized .50BMG cases loaded with 200 grains WC870 topped with Price/Al bullets.