An ammunition supplier testified at trial on Monday that he only provided inert dummy rounds to the western film Rust, where actor Alex Baldwin fatally shot cinematographer Halyna Hutchins in 2021.

However, he was also handling live rounds from another production.

Albuquerque-based movie firearms and ammunition supplier Seth Kenney took the stand at the trial of Rust movie armourer Hannah Gutierrez-Reed, who is charged with involuntary manslaughter and evidence tampering in the death of the cinematographer.

Mr Kenney told a jury he cleaned and repackaged ammunition to Rust that was previously supplied to a production in Texas, handing off a box of 50 inert dummy rounds containing no gunpower to the Rust props supervisor on October 12, 2021.

Rust incident
Santa Fe County Sheriff’s office footage showing actor Alec Baldwin practicing drawing his revolver on the set of the Rust movie (Santa Fe County Sheriff/PA)

Mr Kenney also said he scrubbed the exterior of the rounds and cleaned out residue inside each of them to ensure the tell-tale rattle of a metal pellet inside dummy rounds could be heard for safety purposes.

The outcome of the trial may hinge on testimony about the source of six live rounds discovered on the Rust set — including the one from Mr Baldwin’s gun. The industry and union guidelines expressly prohibited live ammunition on movie sets.

Prosecutors say Gutierrez-Reed is to blame for unwittingly bringing live ammunition on set and that she flouted basic safety protocols for weapons handling. She has pleaded not guilty.

Defence lawyers say their client is being smeared and unfairly scapegoated for problems beyond her control, including Mr Baldwin’s handling of the weapons.

On Monday, they highlighted images of Mr Kenney’s “cluttered” business, a storage system without written inventories, and his “hazy” recollection of his timeline for receiving live rounds for another production.

Mr Baldwin, the lead actor and co-producer on Rust, was separately indicted by a grand jury last month on an involuntary manslaughter charge in connection with the fatal shooting of Ms Hutchins.

He has pleaded not guilty, and his trial is scheduled for July.

Mr Baldwin was pointing the gun at Ms Hutchins during a rehearsal on the set outside of Santa Fe when the gun went off, killing her and wounding director Joel Souza.

In Monday’s testimony, Mr Kenney said he provided Rust props master Sarah Zachry, who also managed weapons and ammunition for the production, with dummy ammunition retrieved from a props storage truck on the Texas set of the television series 1883.

“Did you ever give any live ammunition to Sarah Zachry?” prosecutor Kari Morrissey asked Mr Kenney. He responded: “No.”

Responding to additional questions, Mr Kenney said on Monday that he did not have any ammunition that looked like the live rounds investigators found on the set of Rust.

Rust incident
Santa Fe County Sheriff’s office footage showing actor Alec Baldwin on the set of the movie Rust following the shooting of Halyna Hutchins (Santa Fe County Sheriff/PA)

At the same time, Mr Kenney acknowledged he stored live rounds that were used in a live-ammunition shooting exercise for actors on 1883, arranged at a private ranch of series creator Taylor Sheridan.

Mr Kenney said the live rounds from that shooting exercise were brought back to his shop and stored in a bathroom in a grey plastic container marked “live rounds” outside.

The live rounds were initially provided to 1883 by Gutierrez-Reed’s step-father, the Hollywood sharpshooter and weapons consultant Thell Reed.

Investigators from the Santa Fe sheriff’s office searched Mr Kenney’s Albuquerque supply shop several weeks after the fatal shooting, seizing live rounds that were sent to the FBI for analysis and comparison with live rounds discovered on the set of Rust.

Defence lawyer Jason Bowles has argued that Mr Kenney was not adequately investigated for his role as a Rust supplier.

Mr Bowles on Monday highlighted the fact that the search of Mr Kenney’s business took place about a month after the fatal shooting.

Mr Kenney’s testimony also delved into his disagreements with Gutierrez-Reed about her job performance on the set of Rust in connection with a gun misfire — before the fatal shooting.