Falcon - You actually invite discussion of the various theories on the JFK assasination with termans like “generally accepted” and "supposed to have."
General acceptance of the details of crime is meaningless and irrelevent as there is only one “truth.”
I will refrain, though, as this has been done to death, even on this forum, as I recall.
I don’t remember the headstamp of the cartridges used but they were from one of the lots 600, 6001, 6002 or 6003 of ammunition made by the Western Cartridge Company Divsion of Olin Industries, Inc., at East Alton, Illionis. The lot numbers actually all begin with “WCC-” by the way. The other marking on the box is "DA-23-196-ORD-27, which I believe is a Department of Army contract for this ammo, which was to be given to Greece.
Thru a series of events it ended up back in the U.S. as surplus ammunition. It was made in 1954, and as I recall, had a contract form of “WCC” headstamp.
For more information, you might search the Forum. There have been TV shows, a ridiculous movie, and scores of articles on this incident, including the ballistics involved with it.