Info Vor
I will give more details of this case later and merely mention now that it has never been generally realised that this work of identification was carried out by the War Office, and not by any Home Office or Police experts so it is but fair that honour should be given where it is due. The only other case which has been heard in England in which this type of evidence was used as the vital issue was the case of the shot Cypriot doctor, which was heard in March, 1933. I will also allude to this...
Xs
The same two Bullets shown in Plate XXX, but as viewed with the A portion of the right-hand bullet appears in the right-hand half of the field, and a portion of the left-hand bullet in tbe left half. The striations on the two bullets match exactly nickel-jacketed bullets in Plate XXVI. In both cases the engraving consists of deep major furrows with fine striations in between these major furrows. On each fired bullet the deep furrows have been engraved by the lands, and the striations in between...
Accidental Discharge
One of the commonest causes of shooting fatalities is the accidental discharge of a weapon which was loaded and at full cock, and not a single shooting season passes without some such fatal accidents being reported. Anyone carrying a gun may stumble and drop his gun, when the blow which the latter receives on falling is liable to jar the lock or locks off, and thus cause an accidental discharge. The possibility of this happening is almost too well known to need emphasis, but it may not be out...
M
two different 38 lead revolver bullets both fired bv the same revolver Tbc striations on these bullets are finer than those on the bullets shown in Plates XXX to XXXIII, and consequently a higher magnification has been employed which renders it only possible to show a portion of the bullets in the Plate is situated centrally in the field of view of the microscope. If it has been correctly attached to the holder and the spindle is revolved every part of the bullet can be examined in turn without...
Info Lav
and those portions of the bore which are situated between the grooves are known as lands. Gauge or Calibre- Both types of firearms are classified by the Gauge, or Calibre, of their bores that is by the internal dimension of the barrel A different system of measuring, however, exists for large smooth-bores and rifled arms. Large smooth-bores are measured by the number of Pig. x. Cross-section of a rifled barrel showing the grooves and lands. Pig. x. Cross-section of a rifled barrel showing the...
C
A An unfired 6-35 mm. Cartridge Case B A 6-35 mm. Cartridge Case which was fired in a Pistol with rather a loose chamber Not the expansion of the forward part of tlx- ease. The longitudinal scratch should also be noted C A 6-35 mm. Cartridge which was fired in another Pistol The chamber was tighter and there is less expansion of the case. But there is a longitudinal scratch very similar to that in the case shown in the middle photograph means instantaneous, and is slow compared to the...
The Case Of The Shot Cypriot Doctor 1
The only other occasion on which evidence of firearms identification has been put forward in England in a murder trial as a major issue was in March, 1933, and this case may be of interest as expert evidence was brought forward both by the prosecution and the defence.1 The facts leading up to the trial were briefly as follows. A man named Zemenides, who styled himself as Doctor, was the apparent head of the Cypriot community in London. He had, not to put too fine a point on it, swindled 1 At...
Metallic Fouling And Wear
When a number of shots are fired through a rifle small portions of the outside of the bullet are frequendy removed during its passage down the bore and left adhering to the surface of the bore. At first only the smallest particles of the bullet strip, but these may become almost fused on to the inside of the barrel by the extreme heat generated, and are not easily removed. The uneven projections thus formed scrape the surface of each successive bullet and gradually increase in size until the...
Info Jou
Since 1935 all-metal cartridge cases have been gradually coming into increasing use for shotgun cartridges, although naturally the war put a stop to all such manufacture for a number of years. Some Belgian and British all-metal cartridges, as well as some fired cases, are shown in Plate VII A . Zinc, aluminium and brass are the metals which have been used. All shotgun cartridges have a rim of larger diameter round the extreme edge of the base. This rim fits into a groove at the extreme breech...
Introduction
DURING the past few years it has so happened that I have been called as an expert witness or adviser in various legal cases in which firearms played an important part The experience which I have so gained has convinced me of the widespread ignorance of firearms which exists in quarters in which a correct understanding of the elementary principles of the subject would appear to be essential In fact, all too frequently this ignorance can be described only as' appalling. I feel, therefore, that...
Compared
When evidence of the identity of some particular arm can be established both by the evidence of a fired bullet and that of a fired cartridge case, the question may arise as to which is the more reliable. There can only be one answer both are equally reliable provided both can be put forward in a manner which can be appreciated and understood by a non-technical jury. This is the crux of the whole matter, for it is far more difficult to establish identity by means of a fired bullet than by means...
X 1
effected the task of identifying these revolvers by means of ordinary microscopes and not by a comparison microscope. This shows what can be done by competent experts and emphasises the fact, which should be obvious, that it is not the instrument which effects the identification but the man who uses the instrument. The manner in which the work of identification was conducted and in which the evidence was prepared was a model of how such work should be carried out and such evidence should be...
The Identification Of Firearms By Means Of Fired Cartridge Cases
IN the great majority of cases of murder by shooting there is seldom much doubt as to the weapon which was used, but there are occasions when the definite identification of some particular firearm forges the final link in the chain of proof. In this country the most famous example of this type of evidence is the Gutteridge case, in which the facts were briefly as follows. In a motor-car which had undoubtedly been used by the murderers of P.C. Gutteridge the police found a fired revolver...
Photomicrography
As has already been stated any evidence of identification which is unsupported by photographs cannot be regarded as being anything more than an expression of opinion. Photographs are, accordingly, essential and such as are deemed necessary must be taken through the microscope. Once again it must be emphasised that no higher power than is absolutely necessary to show the detail should ever be used. And in the case of photographs which are to be handed to a non-technical jury this rule is more...
X X X
So let us now turn to a consideration of the principles governing the task of establishing the identity of a particular weapon by means of the secondary markings on fired bullets. These secondary markings consist of a number of parallel striations in the furrows cut by the lands, and also in between these land furrows. These striations are all caused by minute tool, or other marks on the surface of the bore which scratch the outside surface of the bullet as it passes along the bore. In fact,...
Info Qeg
of humidity in different places and in the same place with different weather. The products of combustion, however, can hasten or retard the effects of the humidity of the air. For example, the most potent factor in hastening rusting is one of the products of combustion of the cap composition, and not of the powder, as is popularly supposed. Some types of caps are primed with a composition which contains potassium chlorate. On the cap being fired this substance gives up its oxygen very readily...
R
Range, Blackening, 58, 59 Scorching, 57, 58 Unburnt Powder Grain, 59-67, 68, 69, 70 Rebound Bent, 93, 95 Revolvers, Double Action, 21,99,102,103 Single Action, 21,99 Revolving Stage, 128,174 Rifle Powders see Powders Rifled Arm, Definition of, 13 Arms, Types of, 19-24 Rifles, Military, 20 Rifling, Pitch of, How Measured, 199, 203,204 Types of, 140,141 Rules, Proof, 15 Rust, 81, 82, 83, 84
B The Left Lock of the same Gun
The sear tail hangs below the bottom of the lock plate see arrow and rested on the wood of the stock, thus rendering the gun highly dangerous and peculiarly liable to accidental discharge But as in scorching the range is really so close that for all practical purposes these niceties may be ignored, although it is as well that they should be understood. Blackening with a high-power rifle, such as a service rifle, can occur up to about 9 inches and with a revolver or pistol up to about 6 inches....
A Forensic Microscope with the Comparison Eyepiece in position
The bullets can be seen on their holders, and the two projeccion lamps are attached to the fronts focussed with the microscope. Any markings along that part of the edge will then be seen distinctly. The case is then rotated so that every part of the side can be examined in turn. I have purposely explained the procedure of examination with some detail because the instrument usually adopted and recommended for this work is that known as a Comparison Microscope. Such an instrument really consists...
Marks On The Sides Of Hred Cases
So far we have only considered the marks on the base of a fired cartridge case. But there are sometimes marks on the side of a case which, if not so important as those on the base, can be of help in the task of identifying an arm. So it is essential that their usefulness and their limitations should be appreciated. These marks can really be classified under two main headings Extractor Marks, and Scrapes. Extractor Marks are of two entirely distinct types. The first type is produced by the claw...
Powders
Any firearm is really a machine for controlling the application of force which propels the bullet, or shot charge, through the air. The force necessary for this propulsion is generated by the very rapid production of gases resulting from the combustion of the powder charge and on this account all powders which are used in firearms are termed propellants i, rim-fire Long Rifle 2, -300 Rook Rifle, straight and rimmed case 3, 303 Mark VII, bottle-necked rimmed case and pointed bullet 4, -303 Mark...
Unfired and Fired Bullets
A is an unfired lead 3ik gt revolver bullet. B is a similar bullet which has been fired by a Webley revolver. The Webley typo of rifling 7 grooves, right-hand twist, narrow lands is distinctly engraved on the bullet. The arrow indicates the skid mark. C is an unfired nickel-jacketed 7 63 mm. pistol bullet. And D is a similar bullet fired by a Schwartloze self-loading pistol. The engraving is that of the type oi rifling commonly used in the early models of self-loading pistols 4 grooves, right...
Ejector Marks
I have already referred to the ejector marks which are usually present on cartridges fired from self-loading and automatic weapons. In some weapons the firing-pin is used as an ejector, and in others the next cartridge in the magazine or a part of the magazine, and in weapons of these types there will be no ejector mark. When an ejector mark does exist it is, as a rule, obvious. It may be anything from a thin longitudinal cut to a big gash or indentation in the edge of the case. In some pistols...
Four Fired Bullets showing different types of Rifling Engraving
On the left is a -380 lead revolver bullet with the Smith and Wesson type of engraving 5 grooves, right-hand twist, lands and grooves of equal width . Next is a 0 mm. nickel-jacketed bullet fired froin an Astra self-loading pistol. This bullet fitted the bore tightly and is engraved all round its circumference, the striations made by the grooves being clearly visible between the deep land furrows. The rifling is the Browning type 6 grooves, right-hand twist, narrow lands and wide grooves . Next...
Major Sir Gerald Burrard
The Breech Face of a 6.35 mm. Self-Loading Pistol and the Base of Cartridge which was fired from this pistol The marks on the breech face have been imprinted on the base of the cartridge, and in order to simplify the identification of the different marks and their corresponding imprints they have all been numbered. The following marks arc indicated on the breech face i, a deep indentation possibly caused by an accidental blow with the end of a cleaning rod 2, irregular roughening 3, a large...
Info Qoy
with a particular power it is less easily distinguished if the power is increased. And quite apart from this an increase in power means a corresponding increase in the difficulties of examining either fired cartridge cases or fired bullets. It must always be kept in mind that identification is not established by one single mark, but by the relative positions of a number of marks and consequently the fewer of these marks which can be seen in the field of view simultaneously the greater the...
Other Problems
A problem with which those investigating a crime are frequently confronted is to determine the time which has probably elapsed since the firing of a shot. A weapon may be discovered which may, or may not, have been used by the criminal. The barrel is clearly fouled and so the question arises, is it possible by an examination of the barrel to ascertain with any degree of accuracy the period of time which has elapsed since that weapon was fired Before making any attempt to answer this question it...