On a through wound you would not be able to tell what kind of firearm was used. A FMJ bullet does not expand, and tends to make pretty clean wounds. Still, in the case of a head shot the exit wound is going to be explosive. The Zapruder film clearly shows the exit wound in the forehead.

Remember, this was 1963. Forensics was not as developed as it is today. The point I am making here is that even though there was lots of incompetence going around, that does not mean there was a conspiricy.

I remember in the movie JFK the question was raised "Why did they not put Robert Kennedy in charge of the investigation?" The reason is simple, you never put someone with personal ties to an investigation in charge of the investigation.

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