DOI: 10.5061/dryad.wm37pvmkc
title: Gunshots recorded in an open field using iPod Touch devices

description: Seven different firearms, including four pistols and three rifles, were
 fired at least three times each, in order, at a target located at a
 distance of 45 meters from the shooter, in an open field in Gallatin
 County, Montana.  Sound was recorded from four different iPod
 Touch devices.
description: The iPod Touch devices were running the software Auphonic
 Recorder 1.2.1, which was chosen becasue "all default iOS
 pre-processing is deactivated to get the raw audio signal." The
 settings used were "Uncompressed PCM Audio," a 48 kHz sample
 rate, 16-bit precision, and zero attenuation.  Relative
 locations of the iPods are shown in the image file rangedim.png, and are
 described below. This location represents
 the sound experienced by someone who is being shot at. This locations
 should see early arrival of the bullet and impact noise and the muzzle
 blast, followed by the environmental noise. This
 represents an off-axis location which we expect to be identical to the
 same point symmetrical to the shooting axis. It can also represent a
 nearby location that is not targeted. Similar readings to Mic. 1 are
 expected, with the exception of the bullet noise and impact arrival
 time. This location involves greater a azimuth angle.
 It could represent, for example, the location of a nonshooting law
 enforcement officer and his recording device. At this location, we expect
 different bullet noise arrival characteristics, potentially larger
 environmental reflections, and the impact of the bullet hitting the target
 to be heard after muzzle blast. This location
 represents a posterior location. Due to the asymmetric nature of a muzzle
 blast, reduced amplitude is expected at this location along with a later
 arrival of the bullet impact noise relative to the muzzle
 blast. More information is provided in
 readme.txt.
description: The recordings were started asynchronously, but they can be lined
 up based on the impulse from the first gunshot. The Matlab file,
 create_data.m, is provided to pre-process the data for import into
 Matlab. The following firearems were discharged in
 order: Firearm_ID     Class                 Firearm   
                               Ammunition                                 
             Nominal fps   # of shots 
 Pistol    SigM11A1,       3.8" bbl                         
         124 gr 9mm NATO, STANAG 4090, MEN       1200          
 4 Pistol    Glock 19,          4" bbl           
                          124 gr 9mm NATO, STANAG 4090, MEN      
 1200           3 Pistol    Colt1911A1,     5"
 bbl                                      230 gr 45 ACP, Winchester       
                         835            3 Pistol   
 Sig 220,            4.2" bbl                                    230
 gr 45 ACP, Winchester                               835           
 3 Rifle     AR-15,              18" bbl, 1-7
 twist                     5.56 NATO / M855 62 grain, Lake City         
  n/a             3 Rifle     308W 24",       
  Surgeon custom, 1-10 twist    7.62 NATO, Mk 316 MOD 0 equivalent         
 2600           3 Rifle     308W 18",       
  Tikka T3, 1-10 twist               7.62 NATO, Mk 316 MOD 0 equivalent   
       2500           3