The weapons involved were semiautomatic Llama and Beretta pistols and a Beretta MP M submachine gun with expertly handmade silencers. They consisted of cylindrical aluminum tubes subdivided inside by felt, cardboard, and plastics disks with steel wool packing in the hollow spaces. Experimental testing included 55 test firings of weapons with and without silencers at cadaveric skin from various ranges and measurements of speed, stability, and sound pressure. Wound features were determined primarily by the construction of the silencers. In one case the muzzle imprint resulted from a silenced weapon fired at contact range. In general, silencers decrease bullet energy and accelerate energy release in the target or tissue. Silencer produced wounds were characterized by a reduction or absence of a contact ring (ring of dirt), and in close range and contact wounds, features typical of shots fired at close range were absent, particularly soot deposits and powder tattooing. The demonstration of biological material in the silencer proves the silencer was fired at contact range. 6 figures, 2 tables, and 9 references (Author abstract modified)