Shot Range Determination

114 Pages·1991·3.59 MB·English

by  Prof. Dr. Dr. Karl Sellier (auth.)

6
Forensic Science Progress
Forensic
Science
Progress
Volume 6
Shot Range Determination
By K. Sellier
With 66 Figures
Springer-Verlag
Berlin Heidelberg New York
London Paris Tokyo
Hong Kong Barcelona Budapest
Author
Prof. Dr. Dr. Karl SeIlier
Institut fUr Rechtsmedizin der Universitat
Stiftsplatz 12, W-5300 Bonn, FRG
Editors-in-Chief
Prof. Dr. A. Maehly
Forensic Science Centre, 21 Divett Place
Adelaide 5000 S. A.I Australia
Prof. Dr. R. L. Williams
Ardmore, 9 Meon Road, Boscombe East
Bournemouth BH76PN, England
This volume is a revised and translated version of:
K. Sellier, "SchufJentfernungsbestimmung" Band 7 der Reihe "Arbeitsme
thoden der med. u. naturwiss. Kriminalistik", Schmidt-Romhild-Verlag,
Lubeck 1967 - with permission oft he publisher.
ISBN-13: 978-3-642-76723-4 e-ISBN-13: 978-3-642-76721-0
DOl: 10,1007/978-3-642-76721-0
Library of Congress Catalog Card Number: 86-640073
This work is subject to copyright. All rights are reserved, whether the whole or part of the
material is concerned, specifically the rights of translation, reprinting, re-use of illustrations,
recitation, broadcasting, reproduction on microfilms or in other ways, and storage in
data banks. Duplication of this publication or parts thereof is only permitted under the
provisions of the German Copyright Law of September 9, 1965, in its current version, and a
copyright fee must always be paid. Violations fall under the procecution act ofthe German
Copyright Law.
© Springer-Verlag-Berlin Heidelberg 1991
Softcover reprint of the hardcover 1st edition 1991
The use of general descriptive names, registered names, trademarks, etc. in this publication
does not imply, even in the absence of a specific statement, that such names are exempt from
the relevant protective laws and regulations and therefore free for general use.
Product Liability: The publisher can give no guarantee for information about drug dosage
and application thereof contained in this book. In every individual case the respective user
must check its accuracy by consulting other pharmaceutical literature.
Typesetting: Thomson Press (India) Ltd, New Delhi
2152/3020-543210 - Printed on acid-free paper
Editorial Board
Ass.-Prof. Dr. Dr. Hans-J. Battista
Institut fUr Gerichtliche Medizin der UniversiHit Innsbruck,
Abt. fur Forensische und Chemisch-Analytische Toxikologie,
MullerstraBe 44,6020 Innsbruck / Austria
Dr. B. S. Finkle
Associate Director, Center for Human Toxicology
Research Professor, University of Utah,
417 Wakara Way RM 290, Salt Lake City, Utah 84108 / USA
Dr. H. Kobus
Forensic Science Centre, 21 Divett Place,
Adelaide 5000 / South Australia
Prof. Dr. K. Sellier
Institut fUr Gerichtliche Medizin, Stiftsplatz 13,
W-5300 Bonn / FRG
Prof. Dr. George Sensabaugh
Department of Biomedical & Environmental Health Science,
School of Public Health, University of California, Berkeley,
CA 97420 / USA
Dr. R. N. Totty
Assistant Director, Home Office Forensic Science Laboratory,
Priory House, Gooch Street North,
Birmingham B5 6QQ / United Kingdom
Prof. Dr. Rokus A. de Zeeuw
Rijkuniversiteit, Afd. Toxicologie, Antonius Deusinglaan 2,
9713 AW Groningen / The Netherlands
Editorial
During the years 1962-1965 Interscience Publishers produced a
four-volume series called "Methods in Forensic Science". Since
then no major effort seems to have been made to review the
progress in the rapidly expanding field of forensic science.
Our new series "Forensic Science Progress" represents a
serious effort to take up a neglected venture. The series intends
to cover all aspects of forensic science but does not include
forensic medicine which is well represented in other
publications.
The aim of the publisher and the board of editors is to
produce contributions of high quality by leading scientists in
the field of forensic science. Suggestions for such contributions
from the forensic community at large are of course also very
welcome.
The volumes will not be topic-oriented but will give balanced
views on various aspects of the science. The editors believe that
the forensic worker should be informed about all branches of
the science even if he may very well be specialised in one or few
of them. Ideally, contributions should be from 40-80 type
written pages. Experimental details, except when not published
previously, should be covered by citing the appropriate re
ferences. Polemic passages should be avoided but this does not
include objective criticism.
The publisher has tried to choose an editorial board which is
representative not only of various topics but also of the various
geographical regions of the world.
Editors Publisher
Table of Contents
1 Introduction. .
2 General Section 1
2.1 Ammunitions. 1
2.1.1 Normal Ammunition.
2.1.1.1 Primer Ingredients
2.1.1.2 Powder . . . . 7
2.1.1.3 Bullets and Cases. 7
2.1.2 Shot Shells (Shotgun Cartridges) . 8
2.2 Sequence of Events During Firing . . 11
2.2.1 Diagonal Shots, Deviations from the Normal Pattern
of Powder Soot Blackening. . . . . . . . . . 25
3 Classification of Shot Range Zones. . . . . . 27
3.1 Contact Gunshot (Shot with Muzzle Contact) 27
3.1.1 Contact Shot on Naked Skin. . 27
3.1.1.1 Muzzle Imprint . . . . . . 29
3.1.1.2 Soot in the Bullet's Track. . . 30
3.1.1.3 Powder Particles in the Entrance Hole
and the Bullet's Track. . . . . 31
3.1.1.4 Remarks on the Ranges at Which
the Term Contact Shot is Valid. 31
3.2 Intermediate Range Gunshot 32
3.3 Distant Gunshot . . . . . . . . . . 33
4 Qualitative Detection of the Signs of a Close Range Shot 33
4.1 Detection of Powder Tattooing . . . . . . . 33
4.1.1 Diphenylamine-Sulphuric Acid (OS) Reaction 33
4.1.2 Lunges Reagent. . . . . 34
4.2 Detection of the Soot Element Ph . . . . . 34
5 Morphological Methods of Shot Range Determination 35
5.1 General Principles. . 35
5.2 Infrared Photography. . . . . . . . . . 36
x Table of Contents
5.3 Sheet Printing Methods, Chemical . . . . . . . 37
5.3.1 Sheet Printing Method After Walker and also Mayer
and Wolkart. . . . . . . . . . . 37
5.3.2 Sheet Printing Method After Leszczinski. . 37
5.3.3 Sheet Printing Method After Suchenwirth. . 40
5.4 Sheet Printing Method, Physical (Autoradiography) 40
5.5 Determination from Powder Tattooing. . 42
5.6 Imaging with X-Ray, X-Ray Fluorescence. . . . 43
6 The Sampling Test Method for the Quantitative Determination
of Shot Range . . . . . . . . . . . . . . 44
6.1 Initial Remarks and Underlying Principles 44
6.2 Emission Spectrum Analysis (ESA) . . . 47
6.2.1 General Comments. . . . . . . 47
6.2.2 Choice of Lines for Antimony and Iron 47
6.2.3 Sample Taking. . . . . . . . . 48
6.2.4 Carbon Electrodes, Excitation Conditions. 49
6.2.5 Spectrograph. . . . . . . . . . . 50
6.2.6 Extending the Distance of the Shot Range Determination 51
6.3 Atomic Absorption Spectrography (AAS) . 52
6.3.1 General Comment. . . . . . . . . . 52
6.3.2 Apparatus, Detection Limits . . . . . . 52
6.3.3 Taking the Samples, Preparation for Testing. 53
6.3.4 Comments on the Measuring Technique, Producing
a Calibration Curve . . . . . 56
6.4 Neutron Activation Analyses (NAA). . 56
6.4.4 General Comments and Principle. 56
6.4.2 Method, Results. . . . . . . 58
6.5 Polarography. . . . . . . . . . 60
6.6 Other Methods of Shot Range Determination 61
6.6.1 Range Determination using the Bullet-Wipe Ring. 61
6.7 Possible Errors in Shot Range Determination 63
6.7.1 The Vinogradov Phenomenon. . . . . . . 63
6.7.2 Back-Scattering Effect.. . . . . . . . . 65
6.7.3 "Powder Soot Blackening" from Fragmentation
of Bullets ("Ghost Powder Soot Blackening") . 67
6.7.4 Interference with the Detection of Soot Elements
due to Various Physical and Chemical Effects 68
6.7.5 Changes in the Pattern of Powder Soot
due to a Muzzle Silencer. . . . . . . . 71
7 Shot Range Determination for Shotguns . 73
7.1 General Remarks . . . . . . . 73
7.2 Characteristics of the Barrel, Choke. 73
Table of Contents XI
7.3 Shot Patterns-The Diameter of the Shot Pattern
as a Function of the Range and Other Parameters. . . .. 76
7.3.1 Theory. . . . . . . . . . . . . . . . .. 76
7.3.2 Experimentally Determinated Values of as a Function
(J
of the Shot Range and Other Parameters. . 79
7.4 Practical Procedures of Shot Range Determination
for Shotguns. . . . . . 84
8 References and Further Readings. 88
9 Subject Index . . . . . . . 99
1 Introduction
The range at which a weapon has been fired is an important measurement for the
reconstruction of firearms offenses (murder, suicide, accident). All changes caused
by a shot and which vary according to the distance from the weapon are suitable
in principle for determining this distance. However, some procedures are very
elegant in theory but hardly applicable in practice.
The constructions of ammunition and the sequence of events during a shot are
dealt with first as this knowledge forms a basis for understanding the various
methods. \ The individual zones (classes) of firing distances (contact shot,
intermediate shot, distance shot) are described.
In this connection, the morphological methods for determining the firing
distance are discussed. From the shape and size of the powder residue
distribution (soot stains, powder tattooing) and with the knowledge of the
weapon and ammunition, the distance from the target can be elucidated. In this
chapter, the methods of making an invisible distribution visible are also dealt
with. In order to determine the range of the shot from the appearance of the
wound no complicated apparatus is necessary. One can judge with the naked eye.
These procedures have a great advantage over the methods discussed in the
following chapter in that they give stronger proof. They are more vivid and
convincing for the uninitiated (judge or jury) than abstract measurements
obtained by scientific devices.
Subsequently the so-called random sampling method will be described in
which the range of the shot is not derived from the overall distribution but from
one or more randomly taken samples. In principle, the soot elements (metals from
the primer ingredients) from the sample are measured quantitatively and the
distance of the shot read off from calibration curves. These methods are, in
general, more exact than the morphological ones, in particular they are more
sensitive. This means that the determinable shot range is considerably larger.
In the final chapter, methods of the shot range determination for shotguns are
presented. The distance for shotguns can be found out from the distribution of the
pellets. Since the pellets have a much greater range than the powder residues, shot
range determinations of more than 30 m are possible in favorable cases.
2 General Section
2.1 Ammunition
2.1.1 Normal Ammunition
2.1.1.1 Primer Ingredients
The knowledge of the composition of the primer ingredients is important in that,
with the help of the metals contained therein, the shot range can be determined.
2 2 General Section
1. Historical Background
The first firearms were touched off with a glowing coal and later with a red-hot
iron. Very early on (1378), a match made from loosely spun hemp which had been
soaked in lead acetate solution and subsequently dried was employed. In about
1500, the first flintlock weapons appeared although at first not flint but iron
pyrites was used. Only later was flint or sometimes agate utilized.
The decisive advance in this field concerned with the ignition of the propellant
was made at the beginning of the 19th century, although some of the chemicals
involved had been known for a long time. In 1807, Forsyth developed the first
serviceable primer consisting of a mixture of potassium chlorate and combustible
substances, which ignited when struck. The mixture was used in the form of
pellets, encased in wax. Many combustible substances can be used together with
the oxidant potassium chlorate and inventors tried out various materials (e.g.
1810 Lepage: potassium chlorate 33%, black powder 67%).
The first description of a priming cap to be found in the patents derived from
J. Mason in 1818. The first primer of the kind that is normal nowadays, however,
came from the gunsmith Egg. This construction and the introduction of the
piston by de Bourt in Paris in 1820 completed the development of percussion
ignition. Egg's copper priming cap contained a mixture of 70.6% potassium
chlorate, 17.6% sulfur, and 11.8% charcoal. It was covered with tinfoil and given a
protective coating of varnish. Its first extensive use by military was in 1828 with
the introduction of the Dreyse needle gun. This primer consisted of 52.4%
potassium chlorate with 47.6% antimony sulfide as the combustible material and
to provide the necessary friction. For a long time, experimenters tried to use
fulminate of mercury to ignite a charge. It had been discovered in 1799 by Kunkel
von Lowenstein. The mixtures prepared by Lepage contained this highly brisant
component from quite early on. The initial effect is extremely violent but the
effective explosive power is so localized that a secondary incendiary material is
required to overcome the long distance between the piston and the flash holes.
From 1831, fulminate of mercury was generally an ingredient in the mixtures,
mainly together with potassium chlorate and antimony sulfide.
New developments were made necessary by the introduction of rim fire
cartridges (Flobert 1845). In this type of ammunition, the primer is contained in a
raised metallic rim of the cartridge case. When the firing pin strikes this rim, the
primer is ignited. With this type of cartridge great care must be taken that the
correct strength of impact takes place. When the impact is too heavy there is a
danger of penetration and when it is too light the danger is of malfunction and
firing does not take place. The solution to this problem was to increase the
internal friction on impact by using different primer compositions. To this end,
Sharp produced the following mixture: equal amounts of fulminate of mercury
and black powder with the addition of 25% glass powder. Glass powder is still
used today in the production of small bore cartridges (rim fire).
The usual mixture for rifle cartridges in 1878, that is to say the time of the
highest development of black powder, consisted of (primer of the Frankford