title: Staining in firearm barrels after experimental contact shots.
abstract: After contact shots to the head biological traces inside firearm barrels can be found. This study was conducted to simulate and to evaluate such staining. Five current handguns of four inch barrel length in the calibre .22 long rifle, 7.65mm Browning, 9mm Luger and .38 special were used to perform 24 contact shots on silicone coated, gelatine filled box models using the triple contrast method. The staining was documented by endoscopy and swabs gathered from both ends of the barrel were analysed by quantitative PCR. With the exception of the .22 revolver, all firearms showed distinct staining which decreased from the muzzle to the rear end of the barrel. The pattern was varied, showing droplets, elongated forms or stripes. In 14 of 24 shots, staining reached the chamber. The staining results were comparable to real suicide cases.
authors.affiliation: Institute of Forensic Medicine of the University of Bern, Bühlstrasse 20, CH-3012 Bern, Switzerland. Electronic address: christian.schyma@irm.unibe.ch.
authors.forename: C
authors.initials: C
authors.lastname: Schyma
authors.affiliation: Institute of Forensic Medicine of the University of Bern, Bühlstrasse 20, CH-3012 Bern, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Bauer
authors.affiliation: Institute of Forensic Medicine of the University of Bern, Bühlstrasse 20, CH-3012 Bern, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Brünig
authors.affiliation: Institute of Legal Medicine of the University of Bonn, Stiftsplatz 12, 53111 Bonn, Germany; Institute of Legal Medicine of the University of Kiel, Arnold-Heller-Straße 3, 24105 Kiel, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Courts
authors.affiliation: Institute of Legal Medicine of the University of Bonn, Stiftsplatz 12, 53111 Bonn, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Madea
keywords: Backspatter; Biological traces; Firearm; Gun barrel; Suicide; Wound ballistics