Ballistics: the science behind the attacks

This is Dan’s portion of a collaborative project involving several journalism students at Colorado State University

The full story of the attack on Cori Romero and murder John Jacoby can be found here

Episode 4 of the “Shattered Podcast” features Dan explaining the ballistics results of John Jacoby’s autopsy and the process of following the case

Intro

The attacks on Cori Romero and John Jacoby brought more questions than answers as the aggressors left the scene of the crime in both instances.

In that confusion, family, concerned citizens and investigators look to the hard facts and evidence left behind for clarity. The forensic ballistics, or the science of projectiles and firearms, give us a closer look into what happened on the days John Jacoby and Cori Romero were attacked. ll

WHAT ARE BALLISTICS?

Ballistics is the field of mechanics concerned with the launching, flight behavior and impact effects of projectiles, especially ranged weapon munitions such as bullets.

Any time a firearms related crime or injury occurs, ballistics give investigators a peek into what happened that day. Internal ballistics study what happens inside the firearm, while external ballistics tell us about the trajectory of the projectile once it leaves the barrel. Forensic ballistic investigations can tell us important details like the approximate caliber (diameter of the bore and size of projectile), approximate distance the shot was taken from the point of impact, to even tracing the path of the projectile in a victim to determine the angle and other circumstances affecting the shots that took place. 

POSSIBLE SHOOTER LOCATIONS AND INVESTIGATION OF CRIME SCENES

Jacoby’s case is still open with the Windsor Police Department. This means the police report and photos of the crime scene are unavailable to the public. We headed to the location ourselves to do some surveying.

Advanced reporting student Reed Slater (left) and competition shooter Sam Gilman (right) survey the scene in Weld County.

The crime was committed on an open road with fields surrounding the area and very little commercial or residential traffic. The lack of access to the police report and information on caliber of rounds fired we had to check all possibilities from a sniper to a drive-by shooter.

LONG DISTANCE 600+ YARDS

The dimensions of a .308 Winchester round. The most popular sniper cartridge in the world.

Using mapping and a reliable range finder, we started with potential long-distance shot locations that had cover, concealment and easily accessible egress (escape) routes.

The east side of County Road 15 had little-to-no cover or concealment for nearly 700 yards.

To make precision shots from that distance would require a rifle chambered in .308 Winchester (7.62x51 NATO) at minimum.

A .308 Winchester round has a maximum effective range of 800 yards and is the most popular “sniper” round in the world.

At 500 yards, the projectile would slow more than 900 feet-per-second by the halfway point, but still retain nearly 1,200 square pounds of energy giving the projectile plenty of power. 

MID-RANGE

100-500 YARDS

Next, we moved to the west side of the road where cover and concealment are much easier to find.

Locations like a row of 15 foot holding tanks only 265 yards away, a tree line 330 yards away and a concrete irrigation system that provided great cover and egress was only 220 yards from the point of impact.

This distance opens many more possibilities for calibers fired.

Sam Gilman sets up in a concrete irrigation system with clear and unobstructed sight of the Jacoby scene only 200 yards away.

Though a long-distance rifle could still be used in this scenario, any mid-ranged rifle, such as AR or AK variant platform, can effectively hit from this range.

An AR-15 typically fires a 5.56 NATO round that has a maximum effective range of 600 yards. It comparitively has very little drop until it starts reaching its maximum range. Between 200 and 300 yards, most trained shooters could hit their target.

A magazine of 5.56 NATO cartridges. 

​Photo by Will Porada on Unsplash

An AK-47 style rifle typically shoots a 7.62x39 round with an average maximum effective range of 400 yards. This round is heavier than the 5.56 NATO with less velocity, but it can still effectively hit from the 200-300 yard range that most of our potential shooter spots were located.

POINT BLANK

Our final group is from up close. Point blank range is not an exact distance, but when a projectile can be fired at the center or vital area of a given target and hit it without the shooter having to adjust the elevation of the weapon to account for the effect of gravity on the projectile's trajectory. 

Attackers approaching Romero and Jacoby to fire from point blank range would need to rapidly approach them while they were in motion. This points to the possibility of a "drive-by-shooting".

All of the aforementioned weapons could be used in a point blank attack, but now, pistols are considered. While there are many different pistol calibers in existence, “service calibers” such as 9mm, .40 Smith and Wesson, and .45 ACP are some of the most common used by civilians, military and police alike.

While service pistol ammunitions have a surprisingly far range of lethality, most handguns only have an effecient accuracy range that rarely exceeds 30-50 yards (hunting revolvers with long barrels and scopes notwithstanding).

You would need to get very close in order to effectively put shots on target. The fact that Jacoby received two gun shot wounds, with one to each side of his body, shows the theory of a “drive-by shooting” highly probable.

Similarly, Cori Romero was attacked on a raised road with little-to-no cover nor clear sight for someone to fire from anywhere but point blank.

FORENSIC BALLISTICS EXPERT WEIGHS IN ON JOHN JACOBY AUTOPSY

We were able to contact a ballistics expert and sent him the official Jacoby autopsy report of John Jacoby.

Mark Passamaneck

Mark Passamaneck is a professional mechanical engineer with over 18 years of experience in the forensic field. He runs Entropy Engineering Corp. in Arvada, Colorado.

Passamaneck said in a reply email to Dan Campbell that without a police report or photos (which were unavailable due to the open case), it is difficult to give an absolute analysis.

He claims that despite this, very useful information was still collected by the Medical Examiner's report. There are several items in the autopsy “that push me towards a service caliber pistol round firing FMJ (full metal jacket) at a relatively close range; more than six feet away, but likely within 25 feet,” Passamaneck wrote. 

Passamaneck's expertise was incredibly valuable. He paints a picture of what evidence suggests happened that day in great detail.

“We have two bullet strikes on the victim. One from the victims back left at an upward angle and one from the front left at a slight angle. If a person were attempting to flee attackers on a bike, it would be consistent that the torso would be leaning forward. For the gunshot would in the back, if the victim was riding his bike and being pursued by his attacker(s), the attacker would have been behind and to the left. For the bullet that struck him in the face, it would come from in front and still to the left," he said. 

"This leads to indications that the rounds were fired from a vehicle that was overtaking the victim for the first shot and had passed him for the second shot. The descriptions of the Medical Examiner describe a fairly linear path of both bullets, and both bullets impacted bone. The exit wounds were relatively small, and there was no mention of bullet fragments in the wound paths. This moves one away from JHP (jacketed hollow point) or rifle rounds, which almost all tend leave bullet fragments in the victim. FMJs fired from pistols tend to follow a linear path in soft tissues and after impacting small bones. Such was the case.”

These results give us more clarity on the crime. We can deduce that this was not a rifle round nor was it likely fired from more than 25 feet away. The shooter(s) were likely driving in a car, rather than higher-sitting vehicle such a truck. There is currently no way to confirm how many assailants there were, but the evidence suggesting Jacoby was overtaken from behind by a vehicle while fired upon bring plausible theories of more than one assailant present in the vehicle. Mark claims the angles suggest that more than two rounds were fired. Since there were no projectiles recovered at the scene, there are likely several full metal jacket service caliber rounds still laying in the field to the right side of the ditch Jacoby was discovered in.

WRAP-UP

Cori Romero was viciously attacked April 22, 2015.

John Jacoby was needlessly murdered on May 18, 2015.

Their cases may still be open, but the science of forensic ballistics shows us a greater picture of what happened. The findings of the autopsy report coupled with the revelation that this investigation was done in conjunction with the Larimer County Sheriff’s Department and the FBI suggest these cases are likely connected. The hard work of law enforcement and citizens of Northern Colorado continue as the families of the victims