Get ready to get dirty because registration for the 2010 Hard Corps Race series is underway. The Marine Corps Forces Special Operations Command event tests the athleticism of California-based Marines and their civilian counterparts in a 10-part series that will kick off Feb. 27 with a 26-mile “Bulldog Bike Race” along the Camp Pendleton, Calif., coast. It’s the perfect warmup to the duathlon and triathlon to follow. But you better hope you’re in top shape because the competition will get a lot tougher this year. The number of participates in the “World Famous Mud Run” is expected to double to…