Microscopic scratches on test shot shells were consistent with the spent ammunition recovered from crime scenes in a spring 2013 quadruple homicide, a firearm expert said Friday.

Jason Butell, a firearm examiner at the Johnson County crime lab, testified Friday on the tenth day of the trial of Kyle Flack in Franklin County District Court, 301 S. Main St., Ottawa.

Butell said he compared a total of nine spent shot shells, or lipstick-sized plastic tubes, to several test shots fired at the crime lab with a Winchester 1300 12-gauge pump-action shotgun linked to Flack. He said at least eight of the shot shells must have been fired from the same shotgun, based on markings created by the projection.

Flack, 30, has pleaded not guilty to the 2013 shotgun slayings of four victims. He is charged with capital murder in the deaths of Kaylie Smith Bailey, 21, and her 18-month-old daughter, Lana Bailey. He also is charged with premeditated first-degree murder in the deaths of Andrew Stout, 30, and Steven White, 31, criminal possession of a firearm and misdemeanor sexual battery.

The forensic pathologist who performed the autopsies on the bodies said Stout was shot at least five times, White was shot twice, Kaylie was shot once and Lana was shot once — making a total of at least nine blasts.

Previous testimony from people who spent time with Flack revealed he carried a 12-gauge pump-action shotgun wherever he went. A shotgun cleaning kit was found in his duffel bag in Emporia, where he was detained May 8, 2013, after the adult bodies were found at 3197 Georgia Road in Ottawa.

Winchester 12-gauge PDX1 Defender shot shells and 12-gauge Buck 9 Pellet shot shells, along with bullets, metal pellets and buffer material, were recovered from the outbuilding on the Georgia Road property, as well as from the laundry room trash and master bedroom of the Ottawa residence.

As part of testimony throughout the trial, crime scene investigators have been asked by the prosecution to open numerous evidence envelopes containing pieces of shotgun materials. Butell said he examined the ammunition consistent with the shotgun, including at least three whole lead pellets, 11 copper pellets and eight bullets, shown in photos to jurors Friday.

For the purpose of test fires, Butell said the shotgun’s missing barrel and shoulder stock were simulated using inventory from the crime lab’s library. He said he used the recovered shotgun receiver and tubular magazine, as well as the same type of ammunition.

Demonstrating with the shotgun admitted as evidence Friday, he showed jurors how a shot shell would cycle and then fire through the barrel with a pump-and-push motion.

One of Flack’s defense attorneys, Maban Wright, contested Butell’s findings, saying the first examiner found that the shells could not have been fired from Flack’s shotgun. Butell said the examiner’s notes were not peer reviewed nor verified, and he later returned to the lab to say he was mistaken.

Other testimony Friday came from four City of Emporia waste transfer station employees who recollected just how the shotgun was discovered among the garbage May 8, 2013.

Marciel Hernandez said he was operating a backhoe operator when he spied a partial shotgun, missing the barrel. He said he took it to his supervisor, wiped it clean with a paper towel and then called law enforcement who submitted it to the Johnson County crime lab.

Bethany Stone, a Johnson County forensic scientist specializing in DNA analysis, said a few of Flack’s DNA markers were present on shotgun components, though the shotgun itself also had DNA from the transfer station employees and even the victims.

Wright questioned two unidentified DNA markers that could not be linked to Flack, the transfer station employees or the victims.

Testimony continues Monday. The prosecution said they expect to call two more witnesses that morning, before turning it over to Flack’s defense.

After closing statements, jurors will be instructed to come to a verdict based on evidence presented.

Amelia Arvesen is a Herald staff writer. Email her at aarvesen@ottawaherald.com. Follow her on Twitter at @AmeliaArvesen.