Heckler & Koch MR556A1-SD and MR762A1-SD Rifles | Gun Test

Heckler & Koch's (HK) MR556A1 and MR762A1 are two of the most sought after AR-type rifles today. Check out the testing process for the SD (suppressed) models for the MR556A1 and MR762A1. http://www.tactical-life.com