This Silencer Hazard Map Brief documents the free field blast overpressure hazards from the modular Tuna Cans Blackfin XL rifle silencer fielded on an 8-in barrel 300 BLK bolt action rifle firing subsonic 190gr 300 BLK ammunition in the 12-baffle and 9-baffle configuration, as evaluated in technical Report 6.241 and as tabulated in record numbers 7.1.284 and 7.1.285 in the Rankings, respectively.