MSNBC has not had time to do their homework with the Zimmerman evidence dump [but the WaPo did; see UPDATE]:
But the documents give contradictory assessments of how far away Zimmerman was when he shot Martin.
Lab tests by the Florida Department of Law Enforcement's Orlando operations center concluded that residue tests on Martin's sweatshirt were "consistent with a contact shot" — that is, one in which the muzzle of the weapon is physically touching the victim.
But the autopsy report from the Volusia County (Fla.) Medical Examiner's office reached a different conclusion based on examination of the wound itself, saying, "This wound is consistent with a wound of entrance of intermediate range."
The report doesn't define "intermediate range."
As several commenters explained to us yesterday, when a pistol or rifle is fired the projectile, gunpowder (including unburned powder) and expanding gases all exit the barrel. If the victim is close enough to the barrel, the projectile as well as gunpowder particles and gas residue will end up on, or in, the victim. If the victim is more than a few feet away, the shot is "distant" and only the projectile will make impact [Ref 1, 2].
Intermediate Range Definition: Hot powder grains accompany bullet to wound site & are driven into skin, leaving small red marks on skin - stippling/tattooing
Short & Close Range Definition: Bullet hole, stippling & soot present
Contact Range Definition: Bullet hole, muzzle burn mark & impression of firearm present; loose fit - near contact; cornea of soot may be present where weapon not placed directly against skin
Direct contact is pretty obvious when the gun is against the skin. However, as one report explained, an "intermediate" result would occur even over a distance of an inch or two if the victim was wearing clothing or standing, for example, behind a door because most of the powder and gas would be blocked by the obstacle.
So in the current situation there is no contradiction at all - the FDLE placed the gun directly on Martin's sweatshirt (beneath which he had on a t-shirt); the medical examiner, looking just at the body, saw powder residue and stippling consistent with an intermediate range, which would be explained by the two layers of clothing.
ERRATA: Per the police report (p. 16 .pdf) the bullet casing was recovered in the grass. Someone cared, I don't recall why. I do recall Mr. Turner gloating, however, so this "Told you so" thing must be catching.
UPDATE: The WaPo lead:
Neighborhood watch volunteer George Zimmerman shot Trayvon Martin from a very close range, according to documents a Florida prosecutor released Thursday that indicate a hand-to-hand struggle occurred before the teenager was killed.
A lab report, based on an examination of the two sweatshirts Martin was wearing, found holes and gunshot residue consistent with a “contact shot,” meaning the gun was pressed against Martin’s chest. An autopsy report said that the gunshot wound indicated he was shot from an “intermediate range,” which experts say is between one and 18 inches away.