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I'm confused over the rifle testing.


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This should be a fairly simple thing to resolve, but having recently read the WC testimony by Cortland Cunningham, he seems to say that tests proved that the rifle they found in the book depository did not leave any traces of GSR/nitrate of any kind either hand or face.

This seems to me to be a bit... off.

Are there any other reports of the rifle being test fired for GSR/nitrate testing that debunk Cunnigham?

It just seems odd that they claim to have found zero nitrate particles on the hands or face of the guys test firing a poorly maintained bolt action rifle.

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On 12/3/2021 at 7:17 AM, Tommy Tomlinson said:

This should be a fairly simple thing to resolve, but having recently read the WC testimony by Cortland Cunningham, he seems to say that tests proved that the rifle they found in the book depository did not leave any traces of GSR/nitrate of any kind either hand or face.

This seems to me to be a bit... off.

Are there any other reports of the rifle being test fired for GSR/nitrate testing that debunk Cunnigham?

It just seems odd that they claim to have found zero nitrate particles on the hands or face of the guys test firing a poorly maintained bolt action rifle.

2232 November 1963 23 November 1963 An Introduction to the Jfk Assassination

Oswald's Rifle and Paraffin Tests : The JFK Assassination (22november1963.org.uk)

Three Tests Proved Oswald’s Innocence

Test 1: Spectrographic Analysis

Oswald’s paraffin casts were subjected to two analyses. Spectrographic analysis, the method normally used by the police, showed evidence of barium and antimony on Oswald's hands, but not on his cheek.4

Test 2: Neutron Activation Analysis on Oswald

Spectrographic analysis was considered sufficiently reliable for criminal investigations, but in this case a more incisive test was also used. Neutron activation analysis, which is capable of identifying the presence of substances in quantities much too small to be captured by spectrographic analysis, also showed no incriminating quantities of residues on Oswald’s cheek.5 The result was reported in an internal Warren Commission memo: “At best, the analysis shows that Oswald may have fired a pistol, although this is by no means certain. … There is no basis for concluding that he also fired a rifle.”6

Test 3: Controlled Neutron Activation Analysis

In order to check the validity of the neutron activation analysis of Oswald’s paraffin casts, a controlled test was made. Seven marksmen fired a rifle of the same type as that found on the sixth floor. The standard paraffin test was administered, and the paraffin casts were subjected to neutron activation analysis. All seven subjects showed substantial amounts of barium and antimony on their hands and, more importantly, on their cheeks.7

The absence of significant quantities of residues on Oswald’s cheek meant that he almost certainly had not fired a rifle that day.

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Tommy Tomlinson, Pat Speer's "Chapter 4f: "Casts of Contention", addresses the question you ask (https://www.patspeer.com/chapter4fcastsofcontention). In a riveting detailed narrative Speer goes through how the FBI/Warren Commission sought to discount the validity of the paraffin test on Oswald's cheek which appeared to exonerate Oswald from having fired the Mannlicher-Carcano that day, not only via the sometimes-inaccurate chemical test done Nov 22 but by a later, secretive and highly accurate Neutron Activation Analysis (NAA) testing of it. The Warren Commission cited four things in support of rejection of the validity of the paraffin cheek test in exonerating Oswald from having fired the Mannlicher-Carcano that day: (1) the chemical paraffin cheek test done the first day which appeared to exonerate Oswald from firing a rifle is sometimes unreliable, giving false positives and false negatives, thus not decisive in exculpating Oswald; (2) expert opinions of Cunningham from FBI and Day from the Dallas Police Department that the Mannlicher-Carcano would not eject residue on to the shooter's cheek; (3) claim that the casts had been washed and any later results exonerating Oswald from NAA analyses of those casts were unreliable for that reason (that is: any gunshot residue on Oswald's cheek ejected from firing the rifle was washed away from the paraffin casts such that NAA, while accurate, could not detect what had been washed away from the casts, and that is why the NAA could not find evidence from Oswald's cheek that Oswald had fired the rifle); and (4) the claim you mention, that an FBI man had fired Oswald's rifle and a cheek test afterward had given a negative result.

Your question relates to #4. 

(Speer's argument on #2 is that evidence established that Mannlicher-Carcanos do eject residue when fired, spraying toward the face and cheeks, such that the expert opinions expressed under oath by Cunningham and Day saying they did not think that would happen were simply wrong. On #3, Speer cites data refuting that claim. The #1 point is correct but is not the point at issue.)

On #4, one day before Cunningham testified before the Warren Commission, Cunningham reported that an FBI agent had washed his hands thoroughly, fired the Mannlicher-Carcano, and a paraffin test had come up negative on hands and cheek. This was followed by Cunningham giving his opinion that no residue would be expected to have been ejected from the Mannlicher-Carcano on to the cheek. 

Speer says this last-minute test result presented to the Warren Commission contradicted earlier evidence not presented. Speer:

"On 2-27, Dr. Vincent Guinn of General Atomic, whose early offers of help had been rebuffed by the FBI, but who'd later been contacted by the AEC, returns to center stage. A Jevons to Conrad memo relates: "Today, Dr. Vincent P. Guinn called the FBI Laboratory and spoke to SA John F. Gallagher. He advised that since the assassination a large part of their efforts have been directed to the determination of powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald. He advised that there appears that triple firing of this rifle will leave unambiguous positive tests every time on the paraffin casts. It further appears that washing the casts with diphenylbenzidine does remove one of the characteristic elements (barium) but such washings do not remove all of the other characteristic element in powder residues (antimony). Further be advised that the tests to date indicate that powder residues are deposited on both cheeks of the shooter after the rifle is fired either one time or three times. It appears, he added, that these results can be obtained even if the paraffin casts are made 2 1/2 hours after shooting the rifle providing that the skin of the shooter has not been washed in the meantime. He inquired if any information could be furnished him relating to the actual casts from Oswald. He stated he read about those casts in the newspapers but has no way to confirm the stories. SA Gallagher advised he was not at liberty to discuss this matter. Dr. Guinn asked who in Dallas might be knowledgeable on this subject. He was advised that he could not be given any information relative to these casts at this time."

"(Now, for those who wish to see this for yourself. Here's a digital image of this memo...)

 
 
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"Jevons' memo is incredibly revealing. First, it tells us that, as proposed in the 12-11 FBI/AEC meeting, Guinn was indeed brought on board as an AEC consultant. Second, it tells us that he was tasked with unveiling whether or not Oswald should have had gun shot residue on his cheek, had he been the shooter. Third, it tells us he'd concluded that yes, indeed, he should have. And finally, it tells us that these tests were compartmentalized, and that Guinn was not allowed to know the test results on Oswald's cheek cast, and thus his possible innocence. (One can only assume they'd have no problem with people finding out his possible guilt.)"

(. . .)

"As for conducting gunshot residue tests on the face as well as the hands...that also continued after Guinn's and Gallagher's tests and only gained in acceptance. A 1977 article in the Journal of Forensic Sciences by SS Krishnan asserted that gunshot residue could be found on the hands of those firing a rifle, albeit in quantities less than would normally be found on the hands of one firing a revolver. This finding, of course, could be extended to the cheek of one firing a rifle, which would be roughly the same distance from any gunshot residue as the hands. The 2000 text Current Methods in Forensic Gunshot Residue Analysis confirmed that "The face of the shooter can be sampled on occasions when firearms such as rifles and shotguns are used in the shooting. Test firings have shown that large amounts of GSR (gun shot residue) are deposited in these areas when certain types of weapons are used that cause a condition of blow back toward the chest, face, and hair." This book included the results of a "plume study" conducted in 1994. For this study, various rifles were fired in front of a high speed camera. Without exception, clouds of gun shot residue were captured flying back onto the face of the shooters. A Winchester 70 was included in this study as an example of a typical bolt-action rifle. A photo demonstrating the plume from this rifle is presented below.

"The plume study found that the area of highest gunshot residue concentration after firing such a rifle was "centered over the crook of the support arm and extending slightly backward over the face, forehead, and hair, upon cartridge ejection." In 1995's Crime Scene, Larry Ragle confirms the current acceptance of gunshot residue analysis for the cheek and expands “By design, revolvers can leak…Rifles, depending on their construction and wear, can also leak. There is only one way to determine the leakage capacity of any weapon and that is to collect samples from the hands or face firing the weapon under controlled conditions while using the corresponding ammunition.” Of course, this is precisely the kind of test performed by Guinn and Gallagher back in 1964.

"The acceptance of gunshot residue tests of the face has, in fact, in some ways, surpassed even that of gunshot residue tests of the hands. The Elsevier Encyclopedia of Forensic Sciences, published 2000, notes: "In the case of a living shooter, the gunshot residue may be removed by washing the hands; it may also be rubbed off the hands onto clothing. Because of the possibility that gunshot residue may be deliberately removed or inadvertently lost from a shooter's hands other sources of gunshot residue should be considered. Gunshot residue may be deposited on the face and hair of the shooter or on his clothing. Gunshot residue deposited in these areas will generally be retained longer than gunshot residue of the hands." This, of course, feeds back into the question of why, 8 hours after the shooting, there was plentiful residue on Oswald's hands, but so little residue on his cheek?

"The simplest solution, of course, is that he did not fire a rifle on 11-22-63."

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Thank you fellahs.

I f'ing love you guys... Never disappoint when one of us less educated guys gets stuck in the mire.

I've read Pat's blog "cover to cover" before, and remember the stuff about the paraffin, and the neutron tests, but had no recollection of him going into any detail of the matter of the Carcano allegedly not discharging any residue.

It will certainly be a pleasure to dig back into it. He is a terrific narrator.

I'm no firearms expert, but I have to wonder how a bolt action rapid fire could NOT see some degree of discharge of particles simply from the process of opening the bolt and ejecting the empty cartridge. It seems to be one of the most bizarre claims as far as whitewashing the evidence goes.

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