When the Tec-9 submachinegun is lying on the floor, the bolt is visibly closed. A few seconds later, the bolt is open.
They said the dead Marine had been in the Corps for 4 months. Later they said he left boot camp two months ago. That is impossible. If PFC Salazar was only in for four months, he's only been out of boot camp for 30 days, and definitely not about to "deploy" anywhere from Quantico, as he is not in the fleet. That's if he even if he had the shortest MOS school I know of, but more than likely, he'd still be in MOS school, which there are some at Quantico. If so though, he wouldn't hold armory guard as a job title. It would be student or basic Marine awaiting school(waiting for room to become a student).
The TEC-9 was never a fully automatic submachine gun. It was a semi-automatic pistol, and wasn't able to be converted to full auto. Its predecessor, the KG-9 was easily convertible to full auto, and is the actual gun shown here.
When Ziva and DiNozzo go to pick up "Popeye" Carmado, a MetroLink train passes on the tracks in the background. MetroLink trains are the commuter rail service for the Los Angeles area.
When Franks mentions, toward the beginning, that Rosa had a son, Gibbs is surprised. However, at the end Gibbs tells Tomas that Rosa was already pregnant when they met; and then we find out that Gibbs also killed Tomas' father. So Gibbs evidently had known there was a child in the mix.
On the firing range, Ziva David fires one shot, turns all the way around with the gun, then unloads it, pointing away from the targets. Anybody who has firearms training knows, that you never take a loaded weapon away from the firing line before unloading, and you never point it away from the targets.
Emilio Salazar is described by Ziva as being 12 years old in 2003. His arrest record sheet on screen during this dialogue shows him to have been 17 in 2006. His age is wrong by 2 years.