Firearms, the Law, and Forensic Ballistics

Front Cover......Page 1
Acknowledgments......Page 6
Foreword......Page 8
Preface......Page 10
The Author......Page 12
Table of Contents......Page 14
The Beginnings......Page 20
1.1 Blow-Pipes, Air and Gas Guns......Page 26
1.2 Percussion Ignition......Page 28
1.3 Modern Rim-Fire and Centre-Fire Cartridges......Page 29
1.4 Smokeless Powders and Modern Arms......Page 31
Further Reading......Page 37
2.1 History of Weapons Legislation in Britain......Page 38
2.2 Legislation and Gun Control......Page 40
2.3 Firearms and Crime......Page 57
2.4 The Firearms Consultative Committee......Page 65
2.5.2 Category B - Firearms Subject to Authorisation......Page 67
2.6 Legislation in the US......Page 68
Further Reading......Page 72
3.1 The Pioneers......Page 74
3.2 Experts and Charlatans - The American Experience......Page 75
3.3 Court Battles - The English Experience......Page 77
Further Reading......Page 81
4.1 Hinged Barrel Designs......Page 82
4.2 Hammer Shotguns......Page 83
4.3 Accidental Discharge......Page 84
4.4 Repeating Arms......Page 85
4.5 Magazine Systems......Page 87
4.7 Lever-Action Rifles......Page 89
4.9 Accident by Design......Page 90
4.10 Safety Catches and Internal Safeguards......Page 93
4.11 Decocking Devices and Alternative Designs......Page 94
4.13 Bolt-Action Rifle Safety Catches......Page 99
4.14 Trigger Pulls......Page 100
4.15 Blow-Back and Locked Breech Designs......Page 102
4.16 Gas-Operated Arms......Page 104
4.17 Gas and Air Weapon Designs......Page 107
4.18 Crossbows......Page 109
4.19 Processes Used in the Manufacture of Firearms......Page 110
4.19.1 The Rifling of Barrels......Page 112
4.19.2 Machining Processes......Page 115
4.19.3 Finishing Processes......Page 118
Further Reading......Page 119
5.2 The Efficiency of Energy Transfer......Page 122
5.3 Powders and Pressures......Page 125
5.4 Control of Powder Burning Rates......Page 128
5.5 Drachms and Drams......Page 130
5.7 Primer Formulations......Page 131
5.8 Gunshot Residue Analysis......Page 133
5.9 The Transfer of Marks to Missiles and Cartridge Cases......Page 134
5.11 Recoil and Barrel Flip......Page 138
5.12 Choke Boring of Shotguns......Page 140
5.13 Gauges and Bore Sizes......Page 142
Further Reading......Page 143
6.2 Bullet Stability and Instability......Page 146
6.3 The Bullet’s Flight......Page 147
6.4 Bullet Shape, Sectional Density, and Ballistic Coefficient......Page 148
6.5 External Ballistics and Their Calculation......Page 149
6.6 Accuracy......Page 151
6.7 Fin and Aerodynamic Stabilisation......Page 154
6.8 The Question of Range......Page 155
6.9 The Spent Bullet Myth......Page 157
6.10 Secondary Ejecta......Page 158
6.11 The Behaviour of Shotgun Wadding......Page 159
6.12 Sabot Loadings......Page 160
6.13 Choke Boring - Shotgun Pellet Spread and Velocity......Page 161
6.14 Pellet Deformation within the Bore......Page 168
6.16 Soft and Hard Shot - Shotgun Pellet Ballistics......Page 170
6.17 Steel Shot Loadings......Page 172
6.18 Alternative Non-Lead Materials......Page 173
6.19 Pellet Sizes and Weights......Page 176
6.20 The Propensity for Ricochet......Page 177
6.21 Gunfire and the Sounds Made during the Flight of Missiles......Page 180
Further Reading......Page 183
Terminal/Wound Ballistics and Distance of Firing......Page 188
7.1 Mass, Momentum and Kinetic Energy......Page 189
7.2 Incidence of Ricochet......Page 196
7.3 Consequences of Impact and Penetration......Page 197
7.4 Armour-Piercing Ammunition......Page 202
7.5 Explosive Anti-Armour Munitions......Page 204
7.6 Shotgun Missile Injuries......Page 208
7.7 Expanding Bullets......Page 212
7.8 High-Velocity Wound Effects......Page 221
7.9 Range Determination of Single Missile Injuries......Page 229
Further Reading......Page 232
8.1 The On-Call Rota System......Page 236
8.3 Scene Examination......Page 237
8.3.2 Roles......Page 249
8.4 Initial Examination of the Body......Page 250
8.4.1 The Post-Mortem Examination......Page 251
8.6 The First Samples and Observations......Page 252
8.7 The Wound Sites......Page 254
8.8 Arrow and Crossbow Bolt Injuries......Page 263
8.9 Blank-Operated Tool and Humane Killer Injuries......Page 264
8.10 The Wound Track......Page 265
8.11 Examination of PM Exhibits Back at the Laboratory......Page 277
Further Reading......Page 278
Examination of Exhibits at the Laboratory......Page 288
9.1 Initial Examination of Firearms......Page 290
9.2 Trigger Pulls and Mechanical Tests......Page 294
9.3 Firing Range Tests......Page 298
9.4 Incomplete, Defective and Converted Arms......Page 310
9.5 Recovery of Serial Marks......Page 313
9.5.3 Copper, Brass, German Silver and Other Copper Alloys......Page 315
9.6 Examination of Ammunition......Page 316
9.7 Tear-Gas and Irritant Loadings......Page 318
9.8 Electric Shock Devices and Stun Guns......Page 322
9.9 Recovered Cartridge Cases, Bullets, Pellets and Wadding......Page 324
9.10 Examination of Bullet- or Pellet-Damaged Items......Page 333
9.11 Comparison Microscopy......Page 336
9.12 The Electron Microscope......Page 351
9.13 Analysis of Firearms Discharge Residues......Page 353
9.14 Laboratory Reference Collections......Page 358
Further Reading......Page 360
Presentation of Evidence to the Courts......Page 372
10.1 The Prosecution Witness......Page 374
10.2 The Defence Expert......Page 383
Further Reading......Page 386
Proof Marks and the Proof of Firearms......Page 388
11.1.1 Under 1989 Rules of Proof......Page 395
11.1.2 Under 1925 Rules of Proof......Page 396
11.1.3 Under Rules of Proof Prior to 1904......Page 398
11.3 Belgian Proof Marks......Page 402
11.5 Czech Republic Proof Marks......Page 407
11.6.1 Definitive Proof......Page 408
11.7 German Proof Marks......Page 409
11.7.1 Marks of the Suhl Proof House......Page 412
11.8 Finnish Proof Marks......Page 413
11.10 Italian Proof Marks......Page 414
11.11 Spanish Proof Marks......Page 417
11.12 Yugoslav Proof Marks......Page 419
11.13 The Russian Federation......Page 420
11.14 Choke Markings......Page 421
11.14.2 Austro-Hungarian Empire......Page 422
11.14.3.2 Hunting Weapons......Page 424
11.15 Irish Proof Marks......Page 425
11.16 Swedish Proof Marks......Page 426
11.18 American Proof Marks......Page 427
Further Reading......Page 428
Legal Expressions......Page 430
Useful Conversion Factors......Page 433
Arabic Numbers......Page 434
Alphabetical Codes......Page 436
Number Codes......Page 455
a......Page 458
b......Page 459
c......Page 461
d......Page 462
f......Page 463
h......Page 465
l......Page 466
m......Page 467
p......Page 469
r......Page 470
s......Page 471
t......Page 473
w......Page 474
z......Page 475