DELPHI, Ind. (WANE)— Friday's entire morning court session was marked by the testimony of state witness Melissa Oberg, an Indiana State Police forensic firearm examiner. Oberg came to the conclusion, based on her testing, that the unspent cartridge found near Abby Williams' and Libby German's bodies, came from a gun taken from Richard Allen's home during an October 2022 search of his home. That gun, a .40 cal SIG Sauer handgun, is a big part of what the prosecution believes connects Richard Allen to this case. *"Cartridge " refers to a single round of ammunition. A cartridge is made up of a bullet and it's casing. The bullet is the projectile that comes out when the gun is fired, and the casing is left behind. In this case, it's referred to as a cartridge because it was unspent. Oberg spent the first hour of her testimony explaining how a firearm is examined and the parts of this specific handgun. Since the cartridge found at the scene was unspent, she demonstrated to the courtroom three different ways a cartridge can be cycled through that gun and ejected without being fired. The type of cartridge found at the scene was a Winchester .40 cal Smith & Wesson round. So, that is the type of cartridge Oberg used in her testing. She also explained that cartridges have "individual characteristics," which are from imperfections in the manufacturing process. Before Oberg received the cartridge on Feb. 17, 2017— three days after the girls were found—  it was screened for DNA and fingerprints. "I'm a DNA and fingerprint destroyer," Oberg said on the stand. Oberg said that when she received the cartridge on the 17th, it was in "good condition" and "non-remarkable." She also didn't see any biomaterial on it, indicating that the cartridge had not been laying in the woods long enough to feel the effects of being out in the elements. Oberg also noted three marks on the head of the cartridge that she said were from the ejector. There were also three marks under the rim of the cartridge that she said were created by the extractor. Around 10:30 a.m., the defense asked for a break. Judge Gull granted them 15 minutes.