The biggest issue I have with JFK is one of specificity rather than generality. When a human doesn't know an answer, they make a generalization. That didn't happen with JFK.
When they went into the book depository after the shooting, a military veteran that was then in law enforcement documented in writing that a rifle was recovered. He was really specific, I believe he said it was Argentinian (you can google his paperwork) and that it was a 7.65 Mauser.
Note this quote from the Warren report that discounted his written statements: "Constable Deputy Sheriff Weitzman, who only saw the rifle at a glance and did not handle it, thought the weapon looked like a 7.65 Mauser bolt-action rifle.131 (See chapter V, p. 235.)"
As a gun enthusiast, I read that report and was astounded. If I saw a Mauser at a gun show, I'd be 100% accurate saying "it's a mauser". If I made a generalization out of ignorance, I might say its an 8x57 mauser because that's the stereotypical configuration. But to get down to quoting the most obscure of mauser caliber configurations is specificity, not generality. It would be as if I said it was an 8x50 mauser in a Kurz action with Suhl proof marks and a double square bridge. Making such claims of specificity indicates both my expertise and it indicates by virtue of me citing the obscure, I at least know what the generic alternative is and that this one is different.
On the other hand if I saw a weapon from afar and didn't know much about Carcanos, I could very well make the error that it was a 1904 Mannlicher Schoenauer, a Steyr (the popular modern civilian alternative of JFK's era), or that it was a Dutch Mannlicher or a Hungarian Mannlicher. All of the former would be reasonable and somewhat general errors that would describe a rough outline of a weapon but none of those look like a Mauser and picking the most obscure of Mauser types to describe a Carcano is a very dubious claim with unusual specificity.
