From: mst4298@zeus.tamu.edu (Mitchell S Todd)
Subject: Re: Bullet Velocities
News-Software: VAX/VMS VNEWS 1.41    
Organization: Applied Upyerstemmatey Corp
Date: Fri, 24 Jul 1992 21:24:00 GMT

In article <schuck.711957791@sfu.ca>, Bruce_Schuck@sfu.ca writes...
>One of the componenets of the 'magic' bullet theory is that the bullet
>slowed down as it made each wound and thats why it was so 'pristine'.

>This is a table of data from Charles G Wilbers book "Medicolegal
>Investigation of the President John F Kennedy Murder". Wilber is a
>forensic pathologist.

	A forensic biologist.

>The data is from the sworn testimony of Edgewood Arsenal Employees.

>Location of Bullet         Velocity in fps       Energy in foot pounds

>Muzzle of rifle               2160                      1638
>At 60 yards                   1900                      1268
>After passing through JFK     1779                      1111
>After passing thru rib        1514                       805
>After passing thru wrist      1432                       720

	Actually, Wilber contradicts himself here. Edgewood never
	considered that skin penetration slows a bullet down
	much more than other soft tissues (this wasn't researched
	until after the WC). Research, some of which was done by Wilber
 	himself, indicates that a bullet will decelerate between 120fps
	and 170fps for each layer of skin it penetrates. Just using the
	figures for cutaneous retardation, the bullet would lose between
	240 and 340fps just penetrating the skin on JFK's back and
	throat. Not even considering the internal tissue, the
	amount of velocity lost would be considerably less than 
	Edgewood's estimates. Just considering the skin:

	Location of bullet		Velocity in fps  
	
	Before hitting JFK		1900
	after passing through JFK	1660-1560
	after passing through skin	
	on Connelly's back		1540-1390
	After passing through
	skin on JBC's chest		1420-1220
	After penetrating
	JBC's wrist			1300-1050
	after exiting JBC's
	wrist				1180-880
	entering Connelly's thigh	1060-710				

	If we assume a 100fps loss of velocity through JFK's
	neck tissues (from the Edgewood figures, above), a 200fps loss for
	each of the bones that the bullet breaks (Sturdivan and the
	HSCA), the bullet will lose:

		 340 to 440fps in JFKs neck;
	at least 440 to 540 fps through Connelly's back;
	at least 440 to 540 fps through Connelly's wrist;
		 120 to 170 fps at Connelly's thigh.
	
	These losses sum to between 1340fps and 1690fps, and I have
	yet to count the velocity lost in the bullet's passage
	through the soft tissues in Connelly's chest and wrist.
	Nor have I considered the increased penetrating costs
	of a tumbling bullet. Or the energy loss (thus velocity loss)
	involved in the deformation of the bullet. These could 
	easily sum to 100fps or more.

	The table, this time considering the bone and soft tissue
	damage:

	location of bullet		velocity (fps)
	
	after passing through
	JFK's neck:			1560-1460
	after passing through
	JBC's chest:			1120- 920	
	after passing through
	JBC's wrist:			680 - 380

	The velocity of the bullet as it exits Connelly's wrist
	calculated here is about a half to a fourth of the velocity
	estimated by the WC; therefore the energy would be a fourth
	to an eigth of that calculated by Wilber, or about 180 to
	about 90 foot-pounds.
	

>After passing through Connally's wrist, the energy of the bullet was
>720 foot pounds. Wilber says bullet energy is the key factor in wound
>production.
>To err on the side of caution, Wilber then cut the 720 in half and
>compared it to energy levels of other bullets.

>Bullet                                Energy in foot pounds

>Bullet entering Connally's thigh             360
>..45 Army Auto, muzzle velocity               369
>..38 special, muzzle                          265
>9 mm Luger, muzzle                           345
>..44 special, muzzle                          295
>..22 Winchester Magnum, muzzle                365

>If the 'magic' bullet theory is valid, the bullet striking Connally in
>the thigh should have produced a wound similar to an Army .45 fired at
>at near contact range.

	That is, using Edgewood's estimates. More realistic numbers,
	as I've posted, are much smaller. The energy of the bullet
	as it exited Connelly's wrist would have been at most
	half that of a .22 magnum, and that's being generous.
 	

>In fact, the Connally thigh wound is what you would expect if a bullet
>fragment embedded itself in his thigh, not a complete bullet with
>enough energy left to devestate his thigh.

	So, where is the fragment? the fragment found by Dr Shires
	is far too small to have caused the 1cm wound, and no
	fragment was found on the stretcher, or in Connelly's clothes.
	Further, no appropriately sized fragment was found in the
	limo that is consistent with Connelly's wound.


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