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6 December 1963

From:

To:

Via:

Commanding Officer, U. S. Naval Medical School
The White House Physician

Commanding Officer, National Naval Medical Center

Subj: Supplementary report of Naval Medical School autopsy No. A63-272, John F. Kennedy; forwarding of

1.

All copies of the above subject final supplementary report are forwarded herewith.

FIRST ENDORSEMENT

J. H. STOVER, JR.

6 December 1963

From: To:

Commanding Officer, National Naval Medical Center
The White House Physician

1. Forwarded.

C. B. GALLOWAY

COMMISSION EXHIBIT No. 391-Continued

APPENDIX X

Expert Testimony

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. 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. 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 marksand 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.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

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