  The science of firearms muzzle flash has been dominated by three
perspectives: 1) Does the muzzle flash reveal friendly positions to naked eye
observers so as to draw fire from enemy combatants? 2) Can flash signatures be
recognized by electronic surveillance with sufficient accuracy to identify
source firearms? 3) Is the muzzle flash so bright as to diminish the night
vision of friendly forces during a firefight? This paper addresses a fourth
question: Does the muzzle flash of a specific cartridge provide sufficient
duration and intensity of illumination with visible light to allow observers to
positively identify a shooter's face? The experiment used two shooters firing a
total of 20 shots from a 22 LR semi-automatic pistol. Shooters fired in
randomized order, while eight observers (male US military veterans) attempted
to identify the shooter for each trial shot. The firing range was mostly
darkened with only enough ambient light to safely conduct firing tests at the
direction of a range safety officer. There was not enough ambient light to
identify the shooter's face. Observers correctly identified the shooter 54% of
the time and failed to correctly identify the shooter 46% of the time.
Observers were unanimous that there was no hint of any visible illumination on
the shooter's face provided by the muzzle flash. In cases where the shooter was
correctly identified, observers reported using visual cues such as the
sillhouette of the shooters' hair and slight differences in arm positions when
firing the pistol. Other people in the room (including the author) were in
unanimous agreement that there was no illumination of the shooters' faces from
discharge of a 22 LR pistol.
