FIREARMS AND FIREARMS IDENTIFICATION
Three experts gave testimony concerning firearms and firearms identification: Robert A. Frazier and Cortlandt Cunningham of the FBI, and Joseph D. Nicol, superintendent of the Bureau of Criminal Identification and Investigation of the State of Illinois. Frazier has been in the field of firearms identification for 23 years, following a 1-year course of specialized training in the FBI Laboratory. Cunningham has been in the field for 5 years, having also completed the FBI course. Nicol has been in the firearms identification field since 1941, having begun his training in the Chicago police crime laboratory. Each has made many thousands of firearms identification examinations.[A10-1] Frazier testified on the rifle, the rifle cartridge cases, and the rifle bullets; Cunningham on the revolver, the revolver cartridge cases, the revolver bullets, and the paraffin test; and Nicol on all the bullets and cartridge cases and the paraffin test.[A10-2] Nicol’s conclusions were identical to those of Frazier and Cunningham, except as noted.
General Principles
A cartridge, or round of ammunition, is composed of a primer, a cartridge case, powder, and a bullet. The primer, a metal cup containing a detonable mixture, fits into the base of the cartridge case, which is loaded with the powder. The bullet, which usually consists of lead or of a lead core encased in a higher strength metal jacket, fits into the neck of the cartridge case. To fire the bullet, the cartridge is placed in the chamber of a firearm, immediately behind the firearm’s barrel. The base of the cartridge rests against a solid support called the breech face or, in the case of a bolt-operated weapon, the bolt face. When the trigger is pulled, a firing pin strikes a swift, hard blow into the primer, detonating the priming mixture. The flames from the resulting explosion ignite the powder, causing a rapid combustion whose force propels the bullet forward through the barrel.
The barrels of modern firearms are “rifled,” that is, several spiral grooves are cut into the barrel from end to end. The purpose of the rifling is to set the bullet spinning around its axis, giving it a stability in flight that it would otherwise lack. The weapons of a given make and model are alike in their rifling characteristics; that is, number of grooves, number of lands (the raised portion of the barrel between the grooves) and twist of the rifling. When a bullet is fired through a barrel, it is engraved with these rifling characteristics. For example, all S. & W. .38/200 British Service Revolvers have five grooves and five lands, which twist to the right, and bullets fired through such a revolver will have five groove and land impressions, right twist.
In addition to rifling characteristics, every weapon bears distinctive microscopic characteristics on its components, including its barrel, firing pin, and breech face. While a weapon’s rifling characteristics are common to all other weapons of its make and model (and sometimes even to weapons of a different make or model), a weapon’s microscopic characteristics are distinctive, and differ from those of every other weapon, regardless of make and model. Such markings are initially caused during manufacture, since the action of manufacturing tools differs microscopically from weapon to weapon, and since the tools change microscopically while being operated. As a weapon is used, further distinctive microscopic markings are introduced by the effects of wear, fouling, and cleaning. As Frazier testified:
Q. Can you explain how you are able to come to a conclusion that a cartridge case was fired in a particular weapon to the exclusion of all other weapons?
Mr. Frazier. Yes, sir; during the manufacture of a weapon, there are certain things done to the mechanism of it, which are by machine or by filing, by grinding, which form the parts of the weapon into their final shape. These machining and grinding and filing operations will mark the metal with very fine scratches or turning marks and grinding marks in such a way that there will be developed on the surface of the metal a characteristic pattern. This pattern, because it is made by these accidental machine-type operations, will be characteristic of that particular weapon, and will not be reproduced on separate weapons. It may be a combination of marks that—the face of the bolt may be milled, then it may be in part filed to smooth off the corners, and then, as a final operation, it may be polished, or otherwise adjusted during the hand fitting operation, so that it does have its particular pattern of microscopic marks.
The bolt face of the 139 rifle I have photographed and enlarged in this photograph [Commission Exhibit No. 558] to show the types of marks I was referring to.
* * * * *
The marks produced during manufacture are the marks seen on the bolt face; filing marks, machining marks of the various types, even forging marks or casting marks if the bolt happens to be forged or cast. And then variations which occur in these marks during the life of the weapon are very important in identification, because many of the machining marks can be flattened out, can be changed, by merely a grain of sand between the face of the cartridge case and the bolt at the time a shot is fired, which will itself scratch and dent the bolt face. So the bolt face will pick up a characteristic pattern of marks which are peculiar to it.
* * * * *
* * * [T]he marks which are placed on any bolt face are accidental in nature. That is, they are not placed there intentionally in the first place. They are residual to some machining operation, such as a milling machine, in which each cutter of the milling tool cuts away a portion of the metal; then the next tooth comes along and cuts away a little more, and so on, until the final surface bears the combination of the various teeth of the milling cutter. In following that operation, then, the surface is additionally scratched—until you have numerous—we call them microscopic characteristics, a characteristic being a mark which is peculiar to a certain place on the bolt face, and of a certain shape, it is of a certain size, it has a certain contour, it may be just a little dimple in the metal, or a spot of rust at one time on the face of the bolt, or have occurred from some accidental means such as dropping the bolt, or repeated use having flattened or smoothed off the surface of the metal.
* * * * *
* * * [A]s the blade of a milling machine travels around a surface, it takes off actually a dust—it is not actually a piece of metal—it scrapes a little steel off in the form of a dust—or a very fine powder or chip—that tooth leaves a certain pattern of marks—that edge. That milling cutter may have a dozen of these edges on its surface, and each one takes a little more. Gradually you wear the metal down, you tear it out actually until you are at the proper depth. Those little pieces of metal, as they are traveling around, can also scratch the face of the bolt—unless they are washed away. So that you may have accidental marks from that source, just in the machining operation.
Now, there are two types of marks produced in a cutting operation. One, from the nicks along the cutting edge of the tool, which are produced by a circular operating tool—which produce very fine scratches in a circular pattern. Each time the tool goes around, it erases those marks that were there before. And when the tool is finally lifted out, you have a series of marks which go around the surface which has been machined, and you will find that that pattern of marks, as this tool goes around, will change. In one area, it will be one set of marks—and as you visually examine the surface of the metal, these very fine marks will extend for a short distance, then disappear, and a new mark of a new type will begin and extend for a short distance. The entire surface, then, will have a—be composed of a series of circles, but the individual marks seen in the microscope will not be circular, will not form complete circles around the face of the bolt.
Q. Have you had occasion to examine two consecutive bolt faces from a factory?
A. Oh, yes.
Q. And what did you find on that examination?
A. There would be no similarity in the individual microscopic characteristics between the two bolt faces.
Q. There actually was none?
A. No, there was none.[A10-3]
* * * * *
Q. How are you able to conclude that a given bullet was fired in a given weapon to the exclusion of all other weapons, Mr. Frazier?
A. That is based again upon the microscopic marks left on the fired bullets and those marks in turn are based upon the barrel from which the bullets are fired.
The marks in the barrel originate during manufacture. They originate through use of the gun, through accidental marks resulting from cleaning, excessive cleaning, of the weapon, or faulty cleaning.
They result from corrosion in the barrel due to the hot gases and possibly corrosive primer mixtures in the cartridges used, and primarily again they result from wear, that is, an eroding of the barrel through friction due to the firing of cartridges, bullets through it.
In this particular barrel the manufacturer’s marks are caused by the drill which drills out the barrel, leaving certain marks from the drilling tool. Then portions of these marks are erased by a rifling tool which cuts the four spiral grooves in the barrel and, in turn, leaves marks themselves, and in connection with those marks of course, the drilling marks, being circular in shape, there is a tearing away of the surface of the metal, so that a microscopically rough surface is left.
Then removing part of those marks with a separate tool causes that barrel to assume an individual characteristic, a character all of its own.
In other words, at that time you could identify a bullet fired from that barrel as having been fired from the barrel to the exclusion of all other barrels, because there is no system whatever to the drilling of the barrel. The only system is in the rifling or in the cutting of the grooves, and in this case of rifle barrels, even the cutters wear down as the barrels are made, eventually of course having to be discarded or resharpened.
Q. Have you examined consecutively manufactured barrels to determine whether their microscopic characteristics are identical?
A. Yes, sir; I have three different sets of, you might say, paired barrels, which have been manufactured on the same machine, one after the other, under controlled conditions to make them as nearly alike as possible, and in each case fired bullets from those barrels could not be identified with each other; in fact, they looked nothing at all alike as far as individual microscopic characteristics are concerned. Their rifling impressions of course would be identical, but the individual marks there would be entirely different.[A10-4]
When a cartridge is fired, the microscopic characteristics of the weapon’s barrel are engraved into the bullet (along with its rifling characteristics), and the microscopic characteristics of the firing pin and breech face are engraved into the base of the cartridge case. By virtue of these microscopic markings, an expert can frequently match a bullet or cartridge case to the weapon in which it was fired. To make such an identification, the expert compares the suspect bullet or cartridge case under a comparison microscope, side by side with a test bullet or cartridge case which has been fired in the weapon, to determine whether the pattern of the markings in the test and suspect items are sufficiently similar to show that they were fired in the same weapon. This is exemplified by Frazier’s examination of Commission Exhibit No. 543, one of the cartridge cases found in the Texas School Book Depository Building after the assassination:
Q. Mr. Frazier, we were just beginning to discuss, before the recess, Commission Exhibit 559, which is a picture, as you described it, of Exhibit No. 543 and a test cartridge under a microscope * * *?
Mr. Frazier. Yes, sir.
Q. Could you discuss, by using that picture, some of the markings which you have seen under the microscope and on the basis of which you made your identification?
A. Yes, sir. In the photograph I have drawn some small circles and numbered them, those circles, correspondingly on each side of the photograph. The purpose of the circles is not to point out all the similarities, but to call attention to some of them and to help orient in locating a mark on one with a mark on the opposite side of the photograph. In general the area shown is immediately outside of the firing pin in the bolt of the 139 rifle, on the left side of the photograph, and Commission Exhibit 543 on the right side.
The circles have been drawn around the dents or irregularly shaped ridges, small bumps, and depressions on the surface of the metal in six places on each side of the photograph. It is an examination of these marks, and all of the marks on the face of the breech, microscopically which permits a conclusion to be reached. The photograph itself actually is a substitute to show only the type of marks found rather than their nature, that is, their height, their width, or their relationship to each other, which is actually a mental, visual, comparison on the two specimens themselves.
Q. Referring for a second to this mental, visual, comparison, Mr. Frazier, would a person without firearms training—firearms-identification training—be able to look under a microscope and make a determination for himself concerning whether a given cartridge case had been fired in a given weapon?
A. In that connection that person could look through the microscope. He may or may not see these individual characteristics which are present, because he does not know what to look for in the first place, and, secondly, they are of such a nature that you have to mentally sort them out in your mind going back and forth between one area and the other until you form a mental picture of them in a comparison such as this.
If it was a different type of comparison, of parallel marks or something of that nature, then he could see the marks, but in either instance, without having compared hundreds and hundreds of specimens, he would not be able to make any statement as to whether or not they were fired from the same rifle.
Q. Would you say that this is, then, a matter of expert interpretation rather than a point-for-point comparison which a layman could make?
A. I would say so; yes. I don’t think a layman would recognize some of the things on these cartridge cases and some shown in the photographs as actually being significant or not significant, because there will be things present which have nothing whatsoever to do with the firing of the cartridge case in the gun.
There may be a depression in the primer to begin with, and there are no marks registered at that point as a result of the firing. Unless these things are known to occur, someone may actually arrive at a different conclusion, because of the absence of similar marks.
Q. Now having reference to the specific exhibit before you, which is 559—
A. Yes.
Q. Are all the marks shown in both photographs identical?
A. No.
Q. And could you go into detail on a mark which is not identical to explain why you would get such a result?
A. Well, for instance, between what I have drawn here as circle 4 and circle 5, there is a slanting line from the upper left to the lower right on C-6. This line shows as a white line in the photograph.
On the other side there is a rough, very rough ridge which runs through there, having an entirely different appearance from the relatively sharp line on C-6. The significant part of that mark is the groove in between, rather than the sharp edge of the mark, because the sharp corner could be affected by the hardness of the metal or the irregular surface of the primer and the amount of pressure exerted against it, pressing it back against the face of the bolt, at the time the cartridges were fired. So that you would never expect all the marks on one cartridge case to be identical with all the marks on the other cartridge case.
In fact, you would expect many differences. But the comparison is made on the overall pattern, contour, and nature of the marks that are present.
* * * * *
Q. Again there are dissimilar marks on these two pictures [of the firing-pin depressions on the cartridge case Commission Exhibit No. 543, and a test cartridge case], Mr. Frazier?
A. Yes; there are, for the same reason, that metal does not flow the same in every instance, and it will not be impressed to the same depth and to the same amount, depending on the type of metal, the blow that is struck, and the pressures involved.
Q. Is your identification made therefore on the basis of the presence of similarities, as opposed to the absence of dissimilarities?
A. No, that is not exactly right. The identification is made on the presence of sufficient individual microscopic characteristics so that a very definite pattern is formed and visualized on the two surfaces.
Dissimilarities may or may not be present, depending on whether there have been changes to the firing pin through use or wear, whether the metal flows are the same, and whether the pressures are the same or not.
So I don’t think we can say that it is an absence of dissimilarities, but rather the presence of similarities.[A10-5]
A bullet or cartridge case cannot always be identified with the weapon in which it was fired. In some cases, the bullet or cartridge case is too mutilated. In other cases, the weapon’s microscopic characteristics have changed between the time the suspect item was fired and the time the test item was fired—microscopic characteristics change drastically in a short period of time, due to wear, or over a longer period of time, due to wear, corrosion, and cleaning. Still again, the weapon may mark bullets inconsistently—for example, because the bullets are smaller than the barrel, and travel through it erratically.[A10-6]
The Rifle
The rifle found on the sixth floor of the Texas School Book Depository shortly after the assassination was a bolt-action, clip-fed, military rifle, 40.2 inches long and 8 pounds in weight.[A10-7] Inscribed on the rifle were various markings, including the words “CAL. 6.5,” “MADE ITALY,” “TERNI,” and “ROCCA”; the numerals “1940” and “40”; the serial number C2766; the letters “R-E,” “PG,” and “TNI”; the figure of a crown; and several other barely decipherable letters and numbers.[A10-8] The rifle bore a very inexpensive Japanese four-power sight, stamped “4 x 18 COATED,” “ORDNANCE OPTICS INC.,” “HOLLYWOOD CALIFORNIA,” and “MADE IN JAPAN”[A10-9] and a sling consisting of two leather straps, one of which had a broad patch, which apparently had been inserted on the rifle and cut to length.[A10-10] The sling was not a standard rifle sling, but appeared to be a musical instrument strap or a sling from a carrying case or camera bag.[A10-11] A basic purpose of a rifle sling is to enable the rifleman to steady his grip, by wrapping the arm into the sling in a prescribed manner. The sling on the rifle was too short to use in the normal way, but might have served to provide some additional steadiness.[A10-12]
The rifle was identified as a 6.5-millimeter Mannlicher-Carcano Italian military rifle, Model 91/38.[A10-13] This identification was initially made by comparing the rifle with standard reference works and by the markings inscribed on the rifle.[A10-14] The caliber was independently determined by chambering a Mannlicher-Carcano 6.5 millimeter cartridge in the rifle for fit, and by making a sulfur cast of the inside of the rifle’s barrel which was measured with a micrometer.[A10-15] (The caliber of a weapon is the diameter of the interior of the barrel, measured between opposite lands. The caliber of American weapons is expressed in inches; thus a .30-caliber weapon has a barrel which is thirty one-hundredths or three-tenths of an inch in diameter. The caliber of continental European weapons is measured in millimeters. A 6.5-millimeter caliber weapon corresponds to an American .257-caliber weapon, that is, its barrel diameter is about one-fourth inch.)[A10-16] The identification was later confirmed by a communication from SIFAR, the Italian Armed Forces Intelligence Service. This communication also explained the markings on the rifle, as follows: “CAL. 6.5” refers to the rifle’s caliber; “MADE ITALY” refers to its origin, and was inscribed at the request of the American importer prior to shipment; “TERNI” means that the rifle was manufactured and tested by the Terni Army Plant of Terni, Italy; the number “C2766” is the serial number of the rifle, and the rifle in question is the only one of its type bearing that serial number; the numerals “1940” and “40” refer to the year of manufacture; and the other figures, numbers, and letters are principally inspector’s, designer’s, or manufacturer’s marks.[A10-17]
The Model 91/38 rifle was one of the 1891 series of Italian military rifles, incorporating features designed by Ritter von Mannlicher and M. Carcano. The series originally consisted of 6.5-millimeter caliber rifles, but Model 38 of the series, designed shortly before World War II, was a 7.35-millimeter caliber. Early in World War II, however, the Italian Government, which encountered an ammunition supply problem, began producing many of these rifles as 6.5-millimeter caliber rifles, known as the 6.5-millimeter Model 91/38.[A10-18] The 91/38 has been imported into this country as surplus military equipment, has been advertised quite widely, and is now fairly common in this country.[A10-19]
Like most bolt-action military rifles, the 91/38 is operated by turning up the bolt handle, drawing the bolt to the rear, pushing the bolt forward, turning down the bolt handle, and pulling the trigger. Bringing the bolt forward and turning down the bolt handle compresses the spring which drives the firing pin, and locks the bolt into place. When the trigger is pulled, the cocked spring drives the firing pin forward and the cartridge is fired. The face of the bolt bears a lip, called the extractor, around a portion of its circumference. As the bolt is pushed forward, this lip grasps the rim of the cartridge. As the bolt is pulled back, the extractor brings the empty cartridge case with it, and as the cartridge case is being brought back, it strikes a projection in the ejection port called the ejector, which throws it out of the rifle. Meanwhile, a leaf spring beneath the clip has raised the next cartridge into loading position. When the bolt is brought forward, it pushes the fresh cartridge into the chamber. The trigger is pulled, the cartridge is fired, the bolt handle is brought up, the bolt is brought back, and the entire cycle starts again. As long as there is ammunition in the clip, one need only work the bolt and pull the trigger to fire the rifle.[A10-20]
The clip itself is inserted into the rifle by drawing back the bolt, and pushing the clip in from the top. The clip holds one to six cartridges.[A10-21] If six cartridges are inserted into the clip and an additional cartridge is inserted into the chamber, up to seven bullets can be fired before reloading.[A10-22] When the rifle was found in the Texas School Book Depository Building it contained a clip[A10-23] which bore the letters “SMI” (the manufacturer’s markings) and the number “952” (possibly a part number or the manufacturer’s code number).[A10-24] The rifle probably was sold without a clip; however, the clip is commonly available.[A10-25]
Rifle Cartridge and Cartridge Cases
When the rifle was found, one cartridge was in the chamber.[A10-26] The cartridge was a 6.5-millimeter Mannlicher-Carcano cartridge, manufactured by the Western Cartridge Co., at East Alton, Ill. This type of cartridge is loaded with a full metal-jacketed, military type of bullet, weighing 160-161 grains. The bullet has parallel sides and a round nose. It is just under 1.2 inches long, and just over one-fourth inch in diameter.[A10-27] Its velocity is approximately 2,165 feet per second.[A10-28] The cartridge is very dependable; in tests runs by the FBI and the Infantry Weapons Evaluation Branch of the U.S. Army, the C2766 rifle was fired with this Western Cartridge Co. ammunition over 100 times, with no misfires. (In contrast, some of the other ammunition available on the market for this rifle is undesirable or of very poor quality).[A10-29] The cartridge is readily available for purchase from mail-order houses, as well as a few gunshops; some 2 million rounds have been placed on sale in the United States.[A10-30]
The presence of the cartridge in the chamber did not necessarily mean that the assassin considered firing another bullet, since he may have reloaded merely by reflex.[A10-31]
Commission Exhibit No. 558
Bolt face of the C2766 rifle.
Apart from the cartridge in the rifle, three expended cartridge cases were found in the southeast portion of the sixth floor of the Texas School Book Depository Building, lying between the south wall and a high stack of boxes which ran parallel to the wall.[A10-32] The cartridge cases were a short distance to the west of the southeast corner window in that wall.[A10-33] Based on a comparison with test cartridge cases fired from the C2766 rifle, the three cartridge cases were identified as having been fired from the C2766 rifle.[A10-34] (See Commission Exhibit No. 558, [p. 556].) A test was run to determine if the cartridge-case-ejection pattern of the rifle was consistent with the assumption that the assassin had fired from the southeast window.[A10-35] In this test, 11 cartridges were fired from the rifle while it was depressed 45° downward, and 8 cartridges were fired from the rifle while it was held horizontally. The elevation of the ejected cartridge cases above the level of the ejection port, and the points on the floor at which the ejection cartridge cases initially landed, were then plotted. The results of these tests are illustrated by the diagrams, Commission Exhibits Nos. 546 and 547. Briefly, Commission Exhibit No. 547 shows that with the weapon depressed at a 45° angle, the cartridge cases did not rise more than 2 inches above the ejection port; with the weapon held horizontally, they did not rise more than 12 inches above the ejection port.[A10-36] Commission Exhibit No. 546 shows that if a circle was drawn around the initial landing points of the cartridge cases which were ejected in the test while the rifle was held depressed at 45°, the center of the circle would be located 86 inches and 80° to the right of the rifle’s line of sight; if a circle was drawn around the initial landing points of the cartridge cases ejected while the rifle was held horizontally, the center of the circle would be 80 inches and 90° to the right of the line of sight. In other words, the cartridge cases were ejected to the right of and at roughly a right angle to the rifle.[A10-37] The cartridge cases showed considerable ricochet after their initial landing, bouncing from 8 inches to 15 feet.[A10-38] The location of the cartridge cases was therefore consistent with the southeast window having been used by the assassin, since if the assassin fired from that window the ejected cartridge cases would have hit the pile of boxes at his back and ricocheted between the boxes and the wall until they came to rest to the west of the window.[A10-39]
The Rifle Bullets
In addition to the three cartridge cases found in the Texas School Book Depository Building, a nearly whole bullet was found on Governor Connally’s stretcher and two bullet fragments were found in the front of the President’s car.[A10-40] The stretcher bullet weighed 158.6 grains, or several grains less than the average Western Cartridge Co. 6.5-millimeter Mannlicher-Carcano bullet.[A10-41] It was slightly flattened, but otherwise unmutilated.[A10-42] The two bullet fragments weighed 44.6 and 21.0 grains, respectively[A10-43] The heavier fragment was a portion of a bullet’s nose area, as shown by its rounded contour and the character of the markings it bore.[A10-44] The lighter fragment consisted of bullet’s base portion, as shown by its shape and by the presence of a cannelure.[A10-45] The two fragments were both mutilated, and it was not possible to determine from the fragments themselves whether they comprised the base and nose of one bullet or of two separate bullets.[A10-46] However, each had sufficient unmutilated area to provide the basis of an identification.[A10-47] Based on a comparison with test bullets fired from the C2766 rifle, the stretcher bullet and both bullet fragments were identified as having been fired from the C2766 rifle.[A10-48]
The Revolver
The revolver taken from Oswald at the time of his arrest was a .38 Special S. & W. Victory Model revolver.[A10-49] It bore the serial No. V510210, and is the only such revolver with that serial number, since S. & W. does not repeat serial numbers.[A10-50] The revolver was originally made in the United States, but was shipped to England, as shown by the English inspection or proof marks on the chambers.[A10-51] The revolver showed definite signs of use but was in good operating condition.[A10-52] The revolver was originally designed to fire a .38 S. & W. cartridge, whose bullet is approximately 12 or 13 grains lighter than the .38 Special, and approximately .12 inches shorter, but has a somewhat larger diameter.[A10-53] In the United States, the .38 Special is considered to be a better bullet than the .38 S. & W.,[A10-54] and the revolver was rechambered for a .38 Special prior to being sold in the United States.[A10-55] The weapon was not rebarreled, although the barrel was shortened by cutting off approximately 2¾ of its original 5 inches.[A10-56] The shortening of the barrel had no functional value, except to facilitate concealment.[A10-57]
The weapon is a conventional revolver, with a rotating cylinder holding one to six cartridges. It is loaded by swinging out the cylinder and inserting cartridges into the cylinder’s chambers. If all six chambers are loaded, the weapon can be fired six consecutive times without reloading.[A10-58] To extract empty cartridge cases, the cylinder is swung out and an ejector rod attached to the cylinder is pushed, simultaneously ejecting all the cartridge cases (and cartridges) in the cylinder. If both live cartridges and expended cartridge cases are in the cylinder, before pushing the ejection rod one can tip the cylinder and dump the live cartridges into his hand.[A10-59] The cartridge cases will not fall out, because they are lighter than the cartridges, and when fired they will have expanded so as to tightly fit the chamber walls.[A10-60]
In a crouched stance a person can fire five shots with the revolver in 3-4 seconds with no trouble, and would need no training to hit a human body four times in four or five shots at a range of 8 feet.[A10-61] A person who had any training with the weapon would not find its recoil noticeable.[A10-62]
Revolver Cartridges and Cartridge Cases
When Oswald was arrested six live cartridges were found in the revolver.[A10-63] Three were Western .38 Specials, loaded with copper-coated lead bullets, and three were Remington-Peters .38 Specials, loaded with lead bullets.[A10-64] Five additional live cartridges were found in Oswald’s pocket,[A10-65] all of which were Western .38 Specials, loaded with copper-coated bullets.[A10-66] The Western and Remington-Peters .38 Special cartridges are virtually identical—the copper coating on the Western bullets is not a full jacket, but only a gilding metal, put on principally for sales appeal.[A10-67]
Four expended cartridge cases were found near the site of the Tippit killing.[A10-68] Two of these cartridge cases were Remington-Peters .38 Specials and two were Western .38 Specials.[A10-69] Based on a comparison with test cartridge cases fired in the V510210 revolver, the four cartridge cases were identified as having been fired in the V510210 revolver.[A10-70]
Revolver Bullets
Four bullets were recovered from the body of Officer Tippit.[A10-71] In Nicol’s opinion one of the four bullets could be positively identified with test bullets fired from V510210 revolver, and the other three could have been fired from that revolver.[A10-72] In Cunningham’s opinion all four bullets could have been fired from the V510210 revolver, but none could be positively identified to the revolver[A10-73]—that is, in his opinion the bullets bore the revolver’s rifling characteristics, but no conclusion could be drawn on the basis of microscopic characteristics.[A10-74] Cunningham did not conclude that the bullets had not been fired from the revolver, since he found that consecutive bullets fired in the revolver by the FBI could not even be identified with each other under the microscope.[A10-75] The apparent reasons for this was that while the revolver had been rechambered for a .38 Special cartridge, it had not been rebarreled for a .38 Special bullet. The barrel was therefore slightly oversized for a .38 Special bullet, which has a smaller diameter than a .38 S. & W. bullet. This would cause the passage of a .38 Special bullet through the barrel to be erratic, resulting in inconsistent microscopic markings.[A10-76]
Based on the number of grooves, groove widths, groove spacing, and knurling on the four recovered bullets, three were copper-coated lead bullets of Western-Winchester manufacture (Western and Winchester are divisions of the same company), and the fourth was a lead bullet of Remington-Peters manufacture.[A10-77] This contrasts with the four recovered cartridge cases, which consisted of two Remington-Peters and two Westerns. There are several possible explanations for this variance: (1) the killer fired five cartridges, three of which were Western-Winchester and two of which were Remington-Peters; one Remington-Peters bullet missed Tippit; and a Western-Winchester cartridge case and the Remington-Peters bullet that missed were simply not found. (2) The killer fired only four cartridges, three of which were Western-Winchester and one of which was Remington-Peters; prior to the shooting the killer had an expended Remington-Peters cartridge case in his revolver, which was ejected with the three Western-Winchester and one Remington-Peters cases; and one of the Western-Winchester cases was not found. (3) The killer was using hand-loaded ammunition, that is, ammunition which is made with used cartridge cases to save money; thus he might have loaded one make of bullet into another make of cartridge case.[A10-78] This third possibility is extremely unlikely, because when a cartridge is fired the cartridge case expands, and before it can be reused it must be resized. There was, however, no evidence that any of the four recovered cartridge cases had been resized.[A10-79]
The Struggle for the Revolver
Officer McDonald of the Dallas police, who arrested Oswald, stated that he had struggled with Oswald for possession of the revolver and that in the course of the struggle, “I heard the snap of the hammer, and the pistol crossed my left cheek * * * the primer of one round was dented on misfire at the time of the struggle. * * *”[A10-80] However, none of the cartridges found in the revolver bore the impression of the revolver’s firing pin.[A10-81] In addition, the revolver is so constructed that the firing pin cannot strike a cartridge unless the hammer (which bears the firing pin) has first been drawn all the way back by a complete trigger pull.[A10-82] Had the hammer gone all the way back and then hit the cartridge, it is unlikely that the cartridge would have misfired.[A10-83] It would be possible for a person to interject his finger between the hammer and the cartridge, but the spring driving the hammer is a very strong one and the impact of the firing pin into a finger would be clearly felt.[A10-84] However, the cylinder and the trigger are interconnected and the trigger cannot be fully pulled back if the cylinder is grasped.[A10-85] Therefore, if Oswald had pulled on the trigger while McDonald was firmly grasping the cylinder, the revolver would not have fired, and if the gun was grabbed away at the same time the trigger would have snapped back with an audible sound.[A10-86]
The Paraffin Test
During the course of the interrogation of Lee Harvey Oswald following the assassination a paraffin test was performed by the Dallas police on both of his hands and his right cheek. The paraffin cast of Oswald’s hands reacted positively to the test. The cast of the right cheek showed no reaction.[A10-87]
To perform the paraffin test, layers of warm liquid paraffin, interleaved with layers of gauze for reinforcement, are brushed or poured on the suspect’s skin. The warm sticky paraffin opens the skin’s pores and picks up any dirt and foreign material present at the surface. When the paraffin cools and hardens it forms a cast, which is taken off and processed with diphenylamine or diphenylbenzidine, chemicals which turn blue in the presence of nitrates. Since gunpowder residues contain nitrates, the theory behind the test is that if a cast reacts positively, i.e., if blue dots appear, it provides evidence that the suspect recently fired a weapon.[A10-88] In fact, however, the test is completely unreliable in determining either whether a person has recently fired a weapon or whether he has not.[A10-89] On the one hand, diphenylamine and diphenylbenzidine will react positively not only with nitrates from gunpowder residues, but nitrates from other sources and most oxidizing agents, including dichromates, permanganates, hypochlorates, periodates, and some oxides. Thus, contact with tobacco, Clorox, urine, cosmetics, kitchen matches, pharmaceuticals, fertilizers, or soils, among other things, may result in a positive reaction to the paraffin test. Also, the mere handling of a weapon may leave nitrates on the skin.[A10-90] A positive reaction is, therefore, valueless in determining whether a suspect has recently fired a weapon. Conversely, a person who has recently fired a weapon may not show a positive reaction to the paraffin test, particularly if the weapon was a rifle. A revolver is so constructed that there is a space between the cylinder, which bears the chambers, and the barrel. When a revolver is fired, nitrate-bearing gases escape through this space and may leave residues on the hand.[A10-91] In a rifle, however, there is no gap between the chamber and the barrel, and one would therefore not expect nitrates to be deposited upon a person’s hands or cheeks as a result of his firing a rifle. As Cunningham testified:
Mr. Cunningham. * * * I personally wouldn’t expect to find any residues on a person’s right cheek after firing a rifle due to the fact that by the very principles and the manufacture and the action, the cartridge itself is sealed into the chamber by the bolt being closed behind it, and upon firing the case, the cartridge case expands into the chamber filling it up and sealing it off from the gases, so none will come back in your face, and so by its very nature, I would not expect to find residue on the right cheek of a shooter.[A10-92]
The unreliability of the paraffin test has been demonstrated by experiments run by the FBI. In one experiment, conducted prior to the assassination, paraffin tests were performed on 17 men who had just fired 5 shots with a .38-caliber revolver. Eight men tested negative in both hands, three men tested positive on the idle hand and negative on the firing hand, two men tested positive on the firing hand and negative on the idle hand, and four men tested positive on both their firing and idle hands.[A10-93] In a second experiment, paraffin tests were performed on 29 persons, 9 of whom had just fired a revolver or an automatic, and 20 of whom had not fired a weapon. All 29 persons tested positive on either or both hands.[A10-94] In a third experiment, performed after the assassination, an agent of the FBI, using the C2766 rifle, fired three rounds of Western 6.5-millimeter Mannlicher-Carcano ammunition in rapid succession. A paraffin test was then performed on both of his hands and his right cheek. Both of his hands and his cheek tested negative.[A10-95]
The paraffin casts of Oswald’s hands and right cheek were also examined by neutron-activation analyses at the Oak Ridge National Laboratory. Barium and antimony were found to be present on both surfaces of all the casts and also in residues from the rifle cartridge cases and the revolver cartridge cases.[A10-96] Since barium and antimony were present in both the rifle and the revolver cartridge cases, their presence on the casts were not evidence that Oswald had fired the rifle. Moreover, the presence on the inside surface of the cheek cast of a lesser amount of barium, and only a slightly greater amount of antimony, than was found on the outside surface of the cast rendered it impossible to attach significance to the presence of these elements on the inside surface. Since the outside surface had not been in contact with Oswald’s cheek, the barium and antimony found there had come from a source other than Oswald. Furthermore, while there was more barium and antimony present on the casts than would normally be found on the hands of a person who had not fired a weapon or handled a fired weapon, it is also true that barium and antimony may be present in many common items; for example, barium may be present in grease, ceramics, glass, paint, printing ink, paper, rubber, plastics, leather, cloth, pyrotechnics, oilcloth and linoleum, storage batteries, matches and cosmetics; antimony is present in matches, type metal, lead alloys, paints and lacquers, pigments for oil and water colors, flameproof textiles, storage batteries, pyrotechnics, rubber, pharmaceutical preparations and calico; and both barium and antimony are present in printed paper and cloth, paint, storage batteries, rubber, matches, pyrotechnics, and possibly other items. However, the barium and antimony present in these items are usually not present in a form which would lead to their adhering to the skin of a person who had handled such items.[A10-97]
The Walker Bullet
On April 10, 1963, a bullet was recovered from General Walker’s home, following an attempt on his life.[A10-98] The bullet, which was severely mutilated, weighed 148.25 grains.[A10-99] This bullet had the rifling characteristics of the C2766 rifle and all its remaining physical characteristics were the same as the Western 6.5 millimeter Mannlicher-Carcano bullet. However, while the bullet could have been fired from the C2766 rifle, it was severely mutilated and in Frazier’s opinion could not be identified as having been fired or not fired from that rifle.[A10-100] Nicol agreed that a positive identification could not be made, but concluded there was “a fair probability” that the bullet had been fired from the same rifle as the test bullets.[A10-101]