LNers Can't Explain the Two Back-of-Head Bullet Fragments

[Tim Nickerson]

The first theory, proposed by Tim Nickerson, is that the 2.5 mm fragment “may be” the 3 x 1 mm fragment mentioned in the autopsy report. Nickerson obviously has never bothered to read any of Dr. Mantik’s research on the subject. If he had read that research, he would know that the genuine fragment inside the 6.5 object is 6.3 mm long (some might say 6.4 mm) and 2.5 mm wide, i.e., 6.3 x 2.5 mm. I’ve been referring to this fragment as “the 2.5 mm fragment” for convenience, but its length and width are 6.3 x 2.5 mm. Like all genuine fragments, it is irregular in shape. For most of its length, it is 2 mm wide, and part of its right side is jagged with slivers jutting out here and there. So, no, there’s no way that the 6.3 x 2.5 mm fragment inside the 6.5 mm object could be the 3 x 1 mm fragment that Humes mentioned and removed.

The second theory also comes from Tim Nickerson. This theory is that the McDonnel fragment is Humes’s 3 x 1 mm fragment! Now, if you’re thinking, “wait a minute, how could the 6.3 x 2.5 mm fragment and the McDonnel fragment both be the 3 x 1 mm fragment?”, that’s a very good question. Anyway, let’s continue.

There was no 6.3 x 2.5 mm fragment within the 6.5 mm object.  The small fragment that McDonnel placed medial to and above the 6.5 mm object could be the 3 x 1 mm fragment that Humes removed. It doesn't seem likely that a fragment would have been deposited on the outside of the skull. McDonnel erred in placing the 6.5 mm object on the back of the skull. So, maybe he erred in the placement of that small fragment as well.

[Michael T. Griffith]

More follow-up points:

-- In recent days I've gone back and re-read two papers on JFK's head wounds written by Dr. Joseph Riley, a neuroscientist, and I've found a great deal of worthwhile material. I knew that Riley recognized that two bullets must have hit JFK's head, but I'd forgotten about most of his other observations and arguments.

For example, Riley thoroughly debunks the cowlick entry site, correctly noting that the autopsy photos show intact cerebral cortex under/at the cowlick site that the Clark Panel and the HSCA medical panel claimed is an entry wound. It's worth noting that both Dr. Mantik and Dr. Artwohl have confirmed that the autopsy photos do in fact show intact cerebral cortex, and the location of this intact cerebral cortex is at the location of the cowlick entry wound.

Riley also argues that the skull x-rays contain "clear signs" of an entry wound near the EOP, close to the location described in the autopsy report. He notes, 

When a line is drawn from the original entrance wound described by Humes et al. to the fragment in the right supraorbital ridge, this line corresponds exactly to the cavitation wound. ("What Struck John: A Reinterpretation of the Medical Evidence in the Assassination of John F. Kennedy," http://www.kenrahn.com/Marsh/Autopsy/riley.html)

Riley further argues that when objective measurements are made, the entry wound is located close to the location given by the autopsy doctors:

The impression of "cowlick" in the photograph of the entrance wound in the scalp is simply that, an impression for which there is no empirical evidence. When objective measurements (including those provided by the HSCA) are made, the scalp wound is located near where it was described initially by Humes et al. . . .

The HSCA forensics panel provided an illustration of the back of the head showing the wound in the scalp (first figure, far left) and contended that this illustrated a wound in the "cowlick" area. There are numerous problems with this contention (see Riley, 1992). The single sole objective measurement provided by the HSCA is that the wound was located 13 cm from the first prominent crease in the neck. There are numerous problems with this description (e.g., how can it be 13 cm from the base of the neck and 10 cm above the external occipital protuberance?). However, when 13 cm is measured on a scale drawing (bottom, far left; bar represents 13 cm), the scalp wound is not located even remotely close to the "high" entrance wound. When this location is compared to the X-rays, it corresponds exactly to the point identified above (bottom, far right). ("What Struck John: A Reinterpretation of the Medical Evidence in the Assassination of John F. Kennedy," http://www.kenrahn.com/Marsh/Autopsy/riley.html)

And, Riley goes into great detail to explain the fact that an entry wound near the EOP proves that a second bullet must have hit JFK's head. He notes that the fragments and damage in the cerebral cortex could not have been caused by a bullet that entered at the EOP entry site because the entry wound and cerebral cortex damage are not connected by any fragment trail or cavitation wound.

-- An important point to remember about the rear head entry wound is that Dr. Boswell explained that part of the entry hole was contained in one of the late-arriving skull fragments from Dallas.

-- Only at the very end of his interview with the HSCA medical panel did Dr. Humes finally go along with the now-debunked cowlick entry site. Go read the transcript of that interview. Over and over again Humes refused to budge on the issue and insisted that the location given in the autopsy report was correct. Among other things, he pointed out that the cowlick entry site was nearly 4 inches higher than the EOP site, and he was clearly annoyed that the panel was suggesting he had made such an enormous, inexplicable error.

The two other autopsy doctors, Boswell and Finck, refused to go along with the higher entry point. Indeed, Finck even questioned how the autopsy photo of the back of the head had been authenticated!

-- Re-reading Riley's research has helped me to better understand why the plotters felt compelled to manufacture evidence that would appear to support the cowlick entry site, why the plotters felt compelled to try to discredit the EOP entry site, and why the EOP-to-right-orbit fragment trail described in the autopsy report had to be removed from the skull x-rays.

-- When the autopsy doctors reviewed the autopsy materials for five hours in early 1967, they wrote a report about their review, and in that report they reaffirmed that the autopsy report's EOP entry point was correct. They even said that four of the autopsy photos proved this location was correct. I quote:

The autopsy report states that a lacerated entry wound measuring 15 by 6 mm (0.59 by 0.24 inches) is situated in the posterior scalp approximately 2.5 cm (1 inch) laterally to the right and slightly above the external occipital protuberance (a bony protuberance at the back of the head). . . . Photographs Nos. 15, 16, 42, and 43 show the location and size of the wound, and establish that the above autopsy data were accurate (Attestation of Examination of Autopsy Photographs and Radiographs, 1/26/67, p. 3).

However, in a fascinating omission, the autopsy doctors did not mention the EOP-to-right-orbit fragment trail described in the autopsy report. Humes discussed this fragment trail in detail in his WC testimony (2 H 353-354). Needless to say, a fragment trail from the EOP to the right orbit would be powerful evidence that a bullet struck near the EOP and ranged upward as it fell apart. Yet, oddly enough, after reviewing the autopsy materials for five hours, the autopsy doctors said nothing about this fragment trail in their review report, even though they were clearly trying to defend their autopsy findings. So, they either inexplicably failed to mention a key piece of evidence for their claims about the head shot or that key piece of evidence was no longer on the skull x-rays. 

-- Yes, there most certainly is a 6.3 x 2.5 mm fragment within the 6.5 mm object. It is visible under magnification, and Dr. Chesser has confirmed this. Dr. Mantik has produced a diagram of the fragment (which includes size measurements for reference), and the fragment's metallic content has been verified by multiple OD measurements.

-- It is simply ludicrous, clownish to argue that the McDonnel fragment is the 3 x 1 mm fragment removed by Humes. The McDonnel fragment is less than 1 mm in length and width, so it's three times shorter than the 3 x 1 mm fragment. Dr. Mantik has confirmed the McDonnel fragment's existence and location with OD measurements and high-magnification analysis.

I might add that not one of the members of the HSCA medical panel disputed Dr. McDonnel's discovery of the small fragment on the back of the skull. They disputed two of the conclusions of two of the other expert consultants, but they did not dispute anything that McDonnel said about the small fragment.

[Michael T. Griffith]

WC apologists who refuse to face the fact that there's at least one small back-of-head bullet fragment on the autopsy skull x-rays don't seem to care that no expert on either side has denied this fact. They don't want to acknowledge a back-of-head fragment because they know that such a fragment could not have come from an FMJ bullet.

The fact that the autopsy x-rays show at least one small back-of-head fragment has been acknowledged by everyone from Dr. Joseph Riley to the HSCA medical panel to the Clark Panel to Dr. David O. Davis to Dr. Norman Chase to Dr. Larry Sturdivan. This is the fragment that for many years was misidentified as the lateral-view image of the 6.5 mm object. It is about 1 cm below the debunked cowlick entry site.

-- Dr. Riley acknowledges that a small back-of-head fragment appears on the lateral x-rays. One of Riley's main reasons for arguing that the 6.5 mm object is just behind the right eyebrow is that the small back-of-head fragment does not correspond to the 6.5 mm object in density and brightness, and that therefore the small fragment and the 6.5 mm object must be two different fragments ("The Head Wounds of John Kennedy: One Bullet Cannot Account for the Injuries," The Third Decade, March 1993, pp. 9-10, http://jfk.hood.edu/Collection/Weisberg%20Subject%20Index%20Files/R%20Disk/Riley%20Joe/Item%2004.pdf).

It is important to keep in mind that Riley wrote his two articles on JFK's head wounds in the mid-1990s, before Dr. Mantik's OD measurements were published in the 1998 book Assassination Science. Thus, Riley, like everyone else, assumed that the 6.5 mm object was a bullet fragment and did not realize that the object is not metallic.

-- Dr. John Fitzpatrick, the ARRB's forensic radiologist, acknowledged that there's a small fragment on the back of the skull on the lateral x-rays. Like Riley, he noted that the fragment does not have "anywhere near the density/brightness required for it to correspond" to the 6.5 mm object, and he therefore concluded that "no object directly and clearly corresponding to the bright, 6.5 mm wide radio-opaque object in the A-P x-ray could be identified on the lateral skull x-Rays" (ARRB meeting report, 2/6-7/96, p. 2).

-- The HSCA medical panel acknowledged that the lateral x-rays show a small bullet fragment on the outer table of the skull, 1 cm below the alleged cowlick entry site. However, they did not address the obvious disparity in density and brightness between this small fragment and the 6.5 mm object, and they incorrectly claimed that the small fragment was the lateral view of the 6.5 mm object. Everyone from Riley to Sturdivan to Mantik has taken the panel to task for making this impossible assumption. Notes Riley,

It is inexplicable that the Panel would assert that the large round fragment seen on the frontal x-ray [AP x-ray] corresponds to the fragment near the asserted entrance wound on the lateral x-ray. Comparing the frontal and lateral x-rays demonstrates that it is impossible that the images correspond to the same fragment. ("The Head Wounds of John Kennedy," p. 9, http://jfk.hood.edu/Collection/Weisberg%20Subject%20Index%20Files/R%20Disk/Riley%20Joe/Item%2004.pdf)

Anyway, the point is that the HSCA medical panel did acknowledge the presence of a small bullet fragment on the back of the skull on the lateral x-rays.

-- The Clark Panel, like the HSCA medical panel, claimed that the back-of-head fragment on the lateral x-rays is the 6.5 mm object seen on the AP x-ray, but the Clark Panel did so in a much more oblique, passing manner (Clark Panel report, p. 11).

-- Dr. David O. Davis, one of the HSCA's radiology consultants and the chairman of the Department of Radiology at George Washington University Hospital at the time, identified a bullet fragment on the back of the skull in the lateral x-rays. He said nothing about the fragment's size, but he noted that on the lateral view it was "3-4 cm above the lambda" ("Examination of JFK Autopsy X-Rays," 8/23/78, p. 1, 7 HSCA 222).

On an important side note, Davis also noted that the high fragment trail is 6 cm above and in front of the 6.5 mm object, that the trail extends "“anteriorly from the inner table of the skull at a point approximately 6-cm. antero-superiorly [in front of and above] from the previously described embedded metallic fragment” ("Examination of JFK Autopsy X-Rays," 8/23/78, p. 2, 7 HSCA 223).

-- Dr. Norman Chase, another one of the HSCA's radiology consultants and a radiologist at the New York University Medical Center at the time, acknowledged that the lateral x-rays show a bullet fragment, and he concluded that it was the 6.5 mm object seen on the AP x-ray. Using the AP x-ray as his starting point, Chase stated that "the large metal fragment prominent in the x-ray . . . corresponds to the metal fragment in the rear of the head as evidenced on the lateral view" ("Outside Contact Report," 2/27/78, pp. 1-2, 7 HSCA 281-282, emphasis added).

-- Dr. Larry Sturdivan, who served as a wound ballistics consultant for the HSCA, treats the small back-of-head fragment in a curious manner. In commenting on the HSCA medical panel's findings, he correctly notes that this fragment cannot be the companion image of the 6.5 mm object, and that the 6.5 mm object cannot be an FMJ bullet fragment:

The frontal x-ray of the head . . . shows a nearly circular density near the higher entry site that the panel identified as a bullet fragment deposited on the skull at entry. It appears to be a disk of something as dense as metal, with a small circular "bite" taken out of the lower edge. . . . This second bit of evidence was discussed several times during the meetings of the FPP [the HSCA Forensic Pathology Panel, aka the HSCA medical panel] and is mentioned by Dr. Baden [chairman of the panel] as a "relatively large metal fragment". . . . It is interesting that it was phrased that way, ducking the obvious fact that it cannot be a bullet fragment and is not that near to their proposed entry site. A fully jacketed WCC/MC [FMJ] bullet will deform as it penetrates bone, but will not fragment on the outside of the skull. In the Biophysics Lab tests, most of the test bullets' jackets ruptured about midway through the skulls. . . .

When they break up in the target, real bullets break into irregular pieces of jacket, sometimes complete enough to contain pieces of the lead core, and a varying number of irregular chunks of lead core. It cannot break into circular slices, especially one with a circular bite out of the edge. As radiologist David Mantik points out, . . there is no corresponding density on the lateral x-ray. The slightly lighter area indicated by the FPP as the lateral view of this object is not nearly light enough to be a metal disk seen edge-on [from the side/sideways]. As bright as it is seen flat in the frontal x-ray [AP x-ray], it should be even brighter when seen edge-on in the lateral. If an object is present in only one x-ray view, it could not have been embedded in the President's skull or scalp. (The JFK Myths: A Scientific Investigation of the JFK Assassination, 2005, pp. 184-185)

Now, why is Sturdivan so vague about the small back-of-head fragment? He does not deny its existence. But, he never calls it a fragment. He calls it "the slightly lighter area." He admits that the HSCA medical panel identified it as the 6.5 mm object on the lateral x-rays, and does not dispute the panel's identification and placement of the fragment. However, he does not go beyond observing that the fragment cannot be the lateral image of the 6.5 mm object or of a metal disk. Why the apparent vagueness? Because he has just acknowledged that FMJ bullets will not fragment on the outside of the skull, so he knows that this fragment could not have come from an FMJ bullet. I suspect this is also why he says nothing about the McDonnel fragment.

-- Dr. Mantik points out that the small back-of-head fragment 1 cm below the debunked cowlick entry site is only 3-4 mm thick but that the 6.5 mm object's OD measurement shows that it would be nearly 40 mm thick if it were actually metallic; in contrast, the 7 x 2 mm fragment is 2 mm thick on the lateral x-rays, which is consistent with its OD measurement of 1.44 (JFK Assassination Paradoxes, 2022, p. 24).

In OD measurements, larger numbers mean less density, while smaller numbers mean more density. As mentioned, the 6.5 mm object's OD measurement is an impossible 0.60, 0.84 lower than that of the 7 x 2 mm fragment. Even more revealing, the OD measurement of the four dental fillings combined is 0.76, 0.16 higher than the 6.5 mm object's measurement. Thus, if the 6.5 mm object were a bullet fragment, it would be denser than all four dental fillings combined, an obvious impossibility and a clear indication of forgery.

-- We should remember the fact that the small back-of-head fragment and the 6.5 mm object are at the same vertical level, since the small fragment is actually inside the 6.5 mm object when viewed on the AP x-ray. Nobody knew that the small fragment is visible inside the 6.5 mm object under high magnification until Dr. Mantik discovered this (and confirmed its existence with OD measurements). Placing the small fragment inside the 6.5 mm object ensured that the two objects would align vertically. This is important because if the 6.5 mm object were higher or lower than where it is now, it would not align vertically with the small fragment, and nobody would have ever identified the small fragment as the companion image of the 6.5 mm object, and the forgery of the 6.5 mm object would have been obvious. Dr. Mantik explains this point further:

On the AP X-ray, the authentic metal fragment lay at the anatomic right side of the 6.5 mm object, but it was located entirely inside of the 6.5 mm object. In fact, it appeared that the darkroom worker had positioned his double-exposed 6.5 mm image to precisely match the (anatomic) right border of the authentic metal fragment. Furthermore, by doing so, he had guaranteed that the 6.5 mm image would not be left without a partner image on the lateral X-ray. On the other hand, if he had not matched the 6.5 mm image to an authentic metal fragment, the 6.5 mm object would have had no partner image on the lateral X-ray, and the forgery would have been obvious. (JFK Assassination Paradoxes, pp. 24-25)

This vertical alignment was part of the reason that so many experts erroneously concluded that the two images were the same fragment. For example, the HSCA medical panel noted that the AP x-ray shows the 6.5 mm object to be "in approximately the same vertical plane as in the above-described lateral view" (7 HSCA 109).

The forgery of the 6.5 mm object was not perfect, but it was good enough to fool every expert who examined the x-rays for over three decades. The forgers should have created an object on the lateral x-rays that matched the 6.5 mm object in size, density, and brightness, but this would have required a more complicated double-exposure than the 6.5 mm object, and they may have assumed that placing the 6.5 mm object over the image of the small back-of-head fragment would suffice (it did for over three decades). Plus, the science of optical density analysis of x-rays was barely in its infancy in 1963, so the forgers had no idea that one day a radiation oncologist who also happened to be a physicist would detect their forgery with OD analysis.

-- Obviously, the small back-of-head fragment misidentified as the lateral image of the 6.5 mm object is not the McDonnel fragment. The McDonnel fragment is about 5 cm above the lambda, "lies medial" to "the depressed fracture in the right occipital bone," and is "between the galea and the outer table of the skull" ("Report of G.M. McDonnel," 8/4/78, p. 2, 7 HSCA 218), whereas the other fragment is 3-4 cm above the lambda on the lateral view, is 2.5 cm to the right of the midline on the AP x-ray, is 1 cm below the debunked cowlick entry site, and is on the outer table of the skull.

The McDonnel fragment could not have come from an FMJ bullet and could only be a ricochet fragment. Similarly, the small fragment 1 cm below the debunked cowlick entry site could not have come from an FMJ bullet and could only be a ricochet fragment. These facts prove that more than one gunman fired at JFK.

[Michael T. Griffith]

Well, I see that WC apologists have fallen silent in this thread, because they have no credible explanation for the evidence being presented.

In any case, while re-reading the HSCA medical panel’s report, I discovered—and then remembered!—that the panel not only cited the McDonnel fragment but invoked it as evidence for the cowlick entry site:

In March 1978 Dr. McDonnel of Los Angeles examined the skull films for the panel and reported:

". . . There is elevation of the galea medial and lateral to the area of the fracture and metallic fragment in the occipital region [the 6.5 mm object]. A small metallic fragment is located medial to the location of the spherical metallic fragment and fracture between the galea lying and the outer cranial table."

Such separation of the galea from the outer skull bones often occurs as a result of the dislocation of adjacent bone fragments and is seen in an explosive-type injury to the skull. The location of the metallic fragment inside the galea medial to the defect in the skull representing the initial penetration suggests that this separation commenced on initial impact allowing the tiny above-described missile fragment to be displaced medially within this space created by explosion (between the skull and its overlying galea). (7 HSCA 131-132)

Of course, at least some of the medical panel members should have known that FMJ bullets do not shed fragments when they enter skulls, as their own wound ballistics consultant, Dr. Larry Sturdivan, later pointed out, and as many other forensic and wound ballistics experts observed before Sturdivan made his views known. Moreover, the panel had no good explanation for why the fragment is at least 1 cm from the supposed entry point.

Anyway, the main point is that the HSCA medical panel acknowledged the McDonnel fragment and its location. That fragment could only be a ricochet fragment.

Actually, in theory, the McDonnel fragment could be a fragment from the impact of a frangible bullet. However, there is no entry wound at the fragment's location, and the alleged cowlick entry site 1 cm away has no cavitation wound ("cylinder of disruption" or "wound tunnel") proceeding from it; plus, the lone-gunman theory says that a single FMJ bullet struck JFK's head, not a frangible bullet.

It is interesting that the HSCA medical panel sought to explain the separation of the galea from the outer table by assuming "an explosive-type injury to the skull." High-velocity frangible bullets create "explosive-type" injuries, since they typically explode on impact, whereas low-velocity FMJ bullets do not, and the lone-gunman theory says that the alleged lone gunman used FMJ ammo and a low-velocity rifle.

[Andrew Mason]

WC apologists cannot rationally or credibly explain the two bullet fragments on the back of the head in the JFK autopsy skull x-rays.
....
Just to fully explain the absurdity of the idea that a single FMJ headshot bullet deposited any fragment, big or small, on the outer table of the skull, we need to understand that, according to the WC and its apologists, the nose and tail of this supposed lone headshot bullet were found inside the limousine. Thus, in this fanciful scenario, as the bullet struck the skull, either (1) a cross section of metal from inside the bullet was precisely sliced off to form an object that was perfectly round except for a partial circle cut neatly out of its edge or (2) a piece of the hard jacket was somehow sliced off to form an object that was perfectly round except for a partial circle cut neatly out of its edge. Then, this remarkable fragment abruptly stopped right there on the outer table of the skull, while the nose and tail of the rest of the bullet tore through JFK’s brain, exited the skull, and landed inside the limousine.

The "flakes" are not sliced off the bullet. I don't see why they could not be bullet lead.

I am sure you knew this, but it is important to understand the physics of a bullet impact on the bullet itself.
When a bullet nose hits a hard target, the nose of the bullet stops or slows significantly but the rest of the bullet keeps going as the copper jacket cannot apply sufficient force to stop it.  This causes the bullet jacket to crumple and rupture and the bullet lead to compress.  The mechanical work performed by the bullet on itself in compressing the lead adds energy to the lead and can cause the temperature of the lead to exceed its melting point.  So when the jacket ruptures, some liquid lead sprays into the surroundings, in this case the brain. The liquid lead then strikes matter in the brain that it cannot penetrate and it flattens out.   There were many of these flattened specks of lead throughout the brain and in JBC's wrist wound.  This particular fragment just happens to be the largest.

In 1998, seven years before his 2005 book, Sturdivan explained in an e-mail to researcher Stuart Wexler why the 6.5 mm object could not be a bullet fragment. His explanation is worth repeating:

Sturdivan thought it might be an artifact in the film, which also makes no sense because it is seen on both views.  I don't see where he considered that it was bullet lead. 

[Joe Elliott]

. . .
Sturdivan thought it might be an artifact in the film, which also makes no sense because it is seen on both views.  I don't see where he considered that it was bullet lead.

Here is Sturdivan's quote from his book "The JFK Myths", Chapter Ten (Bungled Autopsy), Page 193:

The projectile would only break into disks is a person were shot by something like a roll of coins. When the break up in the target, real bullets break into irregular pieces of jacket, somethings complete enough to contain pieces of the lead core, and a varying number of irregular chunks of lead core. It cannot break into circular slices, especially one with a circular bite out of the edge. As radiologist David Mantik points out in the book edited by Fetzer, there is no corresponding density on the lateral x-ray. The slightly lighter area indicated by the FPP as the lateral view of the object is not nearly light enough to be a metal disk seen edge on. As bright as it is seen flat in the frontal s-ay, it should be even brighter when seen edge on in the lateral. If an object is present in only one x-ray view, it could not have been embedded in the president's skull or scalp.

A metal fragment that cannot be a bullet fragment and appears on only one view of the x-ray would ordinarily be dismissed as an accidental artifact that somehow found its way to the top of the x-ray cassette, for that single exposure. It isn't unusual to see things fall out of the clothing or hair, especially on the tables in the Medical Examiner's Laboratory. Object such as metal buttons would easily cast a shadow on an x-ray. . . .

In his book, Sturdivan has a picture of the frontal x-ray.

Question: Does anyone have pictures of both x-rays of the skull, one from the front and one from the side?

In any case, Sturdivan does not believe that the same object appears in both x-rays. Hence, it must be an artifact. But we can decide for ourselves, if we can see both x-rays.



By the way, I wonder how old Fetzer is doing these days. I wonder if he consults with Alex Jones on how to hide his wealth from the Sandy Hook parents.

[Tim Nickerson]

Question: Does anyone have pictures of both x-rays of the skull, one from the front and one from the side?

In any case, Sturdivan does not believe that the same object appears in both x-rays. Hence, it must be an artifact. But we can decide for ourselves, if we can see both x-rays.

It's not an artifact, and it's not on the back of the skull. It's the 7 x 2 mm fragment that Humes removed from behind the right eye.

[Andrew Mason]

Here is Sturdivan's quote from his book "The JFK Myths", Chapter Ten (Bungled Autopsy), Page 193:

I was referring to Sturdivan's email to Stuart Wexler that is referred to in the OP in which he acknowledges that the fragment is seen on both xray views. He says it "seems to have great[er] optical density thin-face than it does edgewise":

• "I’m not sure just what that 6.5 mm fragment is. One thing I’m sure it is NOT is a cross-section from the interior of a bullet. I have seen literally thousands of bullets, deformed and undeformed, after penetrating tissue and tissue simulants. Some were bent, some torn in two or more pieces, but to have a cross-section sheared out is physically impossible. That fragment has a lot of mystery associated with it. Some have said it was a piece of the jacket, sheared off by the bone and left on the outside of the skull. I’ve never seen a perfectly round piece of bullet jacket in any wound. Furthermore, the fragment seems to have great optical density thin-face on [the frontal X-ray] than it does edgewise [on the lateral X-ray]….The only thing I can think is that it is an artifact (e-mail from Larry Sturdivan to Stuart Wexler on 9 March 1998).  " [as quoted in Mantik's 2015 article "The John F. Kennedy Autopsy x-Rays: The Sage of the Largest "Metallic Fragment"

In any case, Sturdivan does not believe that the same object appears in both x-rays.

Maybe not when he wrote his book.  He is not an expert in interpreting x-rays and he does not appear to have consulted anyone who is.