It is not clear what sequence of events led to Alec Baldwin accidentally shooting and mutilating cinematographer Halyna HUTCHINS. Industry experts and past tragedies suggest that there are only a few possibilities. 

The obvious possibility is that the actor mistakenly fired a live bullet, thinking it was a blank. This could have happened after being handed either a weapon master or an armorer with the weapon.   

After firing the shot, Baldwin was heard saying: ‘In all my years, I’ve never been handed a hot gun.’

IATSE 44 was the largest union to represent film prop masters. She also said that she was struck by an actual live round and not a blank. 

It is not clear how that live round got into the gun, but there are several options. 

SQUIB LOAD : A real bullet was lodged in a barrel of the gun by Baldwin when he fired a blank 

Baldwin could have had an object stuck in the barrel of his prop gun. It’s also known as a squibload, which is when a cartridge doesn’t fire from the barrel because it’s not strong enough to push it out. 

It is not dangerous by itself and can be fixed if it is safely cleared. However, if someone keeps firing shots from the same gun – whether live or not – it can be extremely dangerous. 

A second round fired behind the stuck bullet can cause the weapon or other people to explode. 

Alec Baldwin is seen sobbing after killing cinematographer Halyna Houtchins on the set for his upcoming movie Rust, Santa Fe, New Mexico on Thursday 

The actor, aged 68, was also seen doubled over in a parking lot with his hands on the ground and his face seemingly distressed. 

The difference between live rounds and blanks is the tip of the cartridge where the lethal bullet is contained is not there on a blank. Sometimes they are replaced with cotton or paper. Dummy bullets, unlike blanks, look like ordinary bullets but aren't meant to contain the metal bullet tip either

The difference between live rounds or blanks is that the tip of a cartridge where the lethal shot is contained is not present on a blank. Sometimes they can be replaced with cotton or other paper. Dummy bullets are not intended to contain the metal bullet tip, but look just like ordinary bullets. 

Baldwin may have pulled the trigger if a real bullet got stuck in the gun while it was loaded with blanks. 

In this scenario, the gun was not properly cleared before it was given to him.

An accidental load of a real bullet, or a part of one, was made, and it was not a blank. 

Baldwin immediately reacted to the firing of the gun by asking why he was given a ‘hot gun’, which means one that contained live bullets. 

The daughter of a soldier, Hutchins grew up on a Soviet military base in the Arctic Circle before going to college in Ukrainian capital Kiev. She later moved first to the U.K. to work on documentary filmmaking

Halyna Houtchins, 42 (left), was shot to death in the Bonanza Creek Ranch shooting incident on Thursday.

This is what happened on the 1993 set of The Crow, where actor Brandon Bruce Lee was shot. 

Although the gun was initially believed to be loaded with blanks, an autopsy revealed that a.44 caliber bullet was found near Lee’s spine. 

Police recovered the dummy shell casings. 

A dummy is not like a blank. It looks more like a live round with the bullet at the tip. 

The difference between live round and blank ammunition is the location at the tip of the cartridge that contains the lethal shot. 

Sometimes they can be replaced with cotton or other paper. 

Dummy bullets look like normal bullets but don’t contain the metal bullet tip.

Blank round hit something else on set, causing shrapnel damage to Hutchins as well as the director.

It is possible that the blank accidentally hit something else, causing it to be damaged, sending pieces flying towards Hutchins. 

Some experts in TV and film set have speculated that Baldwin might have been shooting towards the camera.  

Some film and TV industry experts have speculated that the gun was fired when Halyna was behind the camera - something union rules prevent

Some experts in TV and film have speculated that the gun was shot while Halyna was behind a camera, something union rules prohibit. 

Rhys Muldoon has used guns on the set many times, and believes that even blanks are dangerous. He told the BBC that the first thought he had was that of a close-up shot of an actor firing a gun. The gun has hit the DoP and then something has either landed on the French Flag or the blackbox like a part the camera and hit him. 

However, experts in film say that even in these cases, there should be greater safeguards. 

‘If you are in a line of fire… you would wear a face mask, goggles, and stand behind a Perspex camera to reduce the number of people around it. 

‘What I don’t understand in this instance is how two people have been injured, one tragically killed, in the same event,’ Steven Hall, who has worked on films such as Fury and The Imitation Game, told BBC. 

Others believe that Hutchins may have been at the camera with the director filming a scene that saw Baldwin shooting towards the camera when the round went off.  

“We have a firm rule that no live ammunition should ever be loaded into a prop truck, set, or vehicle at any time. It is impossible. If you see bullets on set they are complete dummy rounds and are in no way functional.

“This goes back at Brandon Lee. There is protocol.  There is protocol.