Gun experts say that the weapon shown in an NBC News report is some kind of shotgun.
He had two semiautomatic pistols and a .223-caliber rifle, law enforcement officials said. He apparently used only the handguns, which were later found in the school. The rifle was found in the vehicle.
Three weapons were recovered from the school: a semi-automatic .223 Bushmaster found in a car in the school parking lot, and a Glock and a Sig Sauer found with Lanza's body, a law enforcement official familiar with the investigation said. The weapons were legally purchased by Lanza's mother, the official said.
Now it turns out that the rifle found in the trunk is not a Bushmaster at all, The police officer is, in gun owner's jargon, cycling a bolt to clear the weapon. An AR uses a charging handle. Gun experts have said that the weapon shown in the video is some kind of shotgun. Here is the news report in which the "long weapon" is shown:
Thanks to weapons masters across the Internet for pointing this out.
Another interesting aspect of the news report pointed out by law enforcement commenters is that the officer seems to be completely mishandling evidence, possibly destroying valuable fingerprints and other clues. Law enforcement commenters have indicated that proper procedure might call for the trunk being sealed with evidence tape and the entire car transported to a main crime lab for examination and evidence gathering, such as dusting for prints.
This follows a bewildering change of story from the authorities as to what weapons were actually used in the shooting. Initial reports indicated "apparently handguns and only handguns," NBC report below:
Then the story changed to it being a rifle used in the shootings, in particular a Bushmaster .223. Lt. Paul Vance of the CT State Police said in a press conference on December 16th:
The weapon that was utilized most of the time during this horrific crime was identified as a Bushmaster AR-15 assault type weapon. It had high-capacity magazines.
This now matches what the coroner, Chief Medical Examiner H. Wayne Carver II, said right after the shooting
"All the wounds that I know of at this point were caused by the long weapon," [the coroner] said...