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Category Archives: Firearms Analysis

Firearm Examinations Go 3D

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People often use the term ballistics when they actually mean firearms examination. Ballistics, in its purest definition, is the flight pattern analysis of things like rocks, bullets, artillery shells, and rockets. But the term ballistics has become the vernacular for firearms examinations.

One of the important analyses that takes place in many homicide investigations, is a comparison of bullets removed from a corpse with those test fired by a suspect weapon. As the bullet travels down the barrel, scratches and grooves are cut into the outside of the bullet by the spiral rifling within the barrel and these apply unique characteristics to the bullet. If the test-fired bullet and the bullet removed from the victim can be matched in this fashion, it suggests that the bullet came from that gun to the exclusion of all others.

But, it’s not that simple. During the manufacturing process of the barrel, a tool is used to mold the shape the barrel’s lumen or to hollow out its interior. This process creates the bullet’s pathway from the firing chamber to the muzzle and also adds the rifling characteristics of the weapon’s barrel. Each is different since the molding or cutting process varies with each attempt.

As a tool is used to manufacture barrel after barrel, the tool itself also changes. It is worn, chipped, grooved, and damaged with each use. Think about your kitchen knives. Over time they become dull and must be resharpening. This is because the tool – – the kitchen knife – – itself is altered with each use. This means that as barrels are produced by a particular manufacturing tool, each will be slightly different. However, if two barrels are made by the same tool consecutively, the differences can be so small as to be undetectable. This could lead to false matches.

The same is true of the gun barrel as it is used. With each firing, the grooves are microscopically altered. If a bullet is obtained from the crime scene and is compared to one test fired from the actual murder weapon, it might not match if the weapon has been fired many times between the killing and its discovery. The barrel is altered each time a bullet passes through it and this can be enough to make a match impossible.

To help examiners, the National Institute of Standards and Technology (NIST) has developed a database of 3-D images which will hopefully help examiners be more accurate in their assessments. Obviously, this data will be subject to the same vagaries as described above but with these clearer, three-dimensional images some of the confusion might be reduced and matches might be more accurate down the road. This will be interesting to keep an eye on.

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Q&A with Expanded Audio Discussions Now on the Suspense Magazine Website

Q&A with Expanded Audio Discussions Now on the Suspense Magazine Website

Check out the new posts John Raab of Suspense Magazine and I put together. Read the Q&As and listen to the expanded discussions. Hope each proves helpful for your crime fiction.

Can DNA Be Used To Identify Multiple Assailants In a Three Decade Old Rape?

http://suspensemagazine.com/blog2/2016/12/20/d-p-lyles-forensic-file-episode-1/

In 1863, Could An Autopsy Accurately Determine the Cause of Death?

http://suspensemagazine.com/blog2/2017/01/09/in-1863-could-an-autopsy-accurately-determine-the-cause-of-death-d-p-lyle-answers-this/

Can My Female Character Cause Her Pregnancy To Become “Stone Baby” By Shear Will?

http://suspensemagazine.com/blog2/2016/12/31/can-my-female-character-cause-her-pregnancy-to-become-stone-baby-by-sheer-will/

More to come.

Want more cool questions from crime writers? Check out my three Q&A books.

M&M 200X300

More Info and List of Included Questions

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More Info and List of Included Questions

MF&F 200X320

More Info and List of Included Questions

 

Crime and Science Radio: Forensic Science Then and Now: an Interview with Forensic Scientist Jay Jarvis

Join Jan Burke and Dr. Doug Lyle for an interview with prominent forensic scientist Jay Jarvis, who has over 35 years of experience in working in the field. He has served on the American Society of Crime Lab Directors/Laboratory Accreditation Board, and has written a history of the establishment of the first crime lab in Georgia. He currently operates a private forensic lab, Arma Forensics, which specializes in firearms evidence, and is active in his church and community. He’ll talk to us about forensic science, past, present and future; lab accreditation; firearms evidence; private labs, and more.

 

Jarvis headshot

 

BIO: Jay Jarvis is a native of Long Island, New York. While a student in high school, his chemistry class went on a tour of the New York City Police Crime Lab. It was on that trip that Jay decided that his interest in chemistry could be best used in the field of forensic science. After his family relocated to Georgia, Jay earned his Bachelor of Science degree in Chemistry from Georgia College. To better prepare himself for a career in forensic science, Jay applied for and was accepted into the graduate program in Forensic Chemistry at the University of Pittsburgh and received his Master of Science degree in 1979. Immediately after graduate school, he was hired at the Georgia State Crime Laboratory in Atlanta.

During his 32 plus year career, Jay either performed casework in or was a supervisor for most of the forensic disciplines. Between 1982 and 1997, he wore a multitude of hats, performing casework in firearms and tool marks, hair, fiber and glass comparisons, footwear and tire tread examinations, fire debris and explosives analysis, latent fingerprint processing, marijuana identification, presumptive blood testing and crime scene analysis for a large area of central Georgia. He has testified as an expert in Federal Court and the courts of Georgia and several other states over 750 times.

 

test fire rifle

 

Jay also has extensive experience in crime laboratory accreditation, having served as an accreditation assessor and as a member of the Board of Directors of the American Society of Crime Laboratory Directors Laboratory Accreditation Board (ASCLD/LAB), including one year as the Board Chair. He has been invited to speak at seminars and training sessions on topics related to forensic science. Jay currently lives in northwest Georgia just outside the metropolitan Atlanta area, which allows him easy access to most destinations via Atlanta’s Hartsfield-Jackson International Airport.

LISTEN: http://www.blogtalkradio.com/suspensemagazine/2016/03/25/crime-and-science-radio-with-special-guest-jay-jarvis

Link goes live Saturday June 4, 2016 at 10 a.m. Pacific

LINKS:

Georgia’s Crime Doctor http://www.lulu.com/us/en/shop/jay-jarvis/georgias-crime-doctor/hardcover/product-10639368.html

Arma Forensics http://www.armaforensics.com/index.html

Crime Lab Report  http://forensicfoundations.com/crimelabreport

ASCLD/LAB http://www.ascld-lab.org

“Real-Life Not Like CSI on Television,” Macon Telegraph article on Jay Jarvis http://www.armaforensics.com/uploads/Real_Life_CSI-Grisamore.pdf

“Alumnus carries microscope into career,” Georgia College Alumnus article on Jay Jarvis

http://www.armaforensics.com/uploads/Alumnus_carries_microscope.pdf

 

Crime and Science Radio: Things That Go Boom in the Night: An Interview with Weapons and Explosives Expert and Author John Gilstrap

High Resolution Author Photo

BIO: John Gilstrap is the New York Times bestselling author of Friendly Fire, Nick of Time, Against All Enemies, End Game, Soft Targets, High Treason, Damage Control, Threat Warning, Hostage Zero, No Mercy, Nathan’s Run, At All Costs, Even Steven, Scott Free and Six Minutes to Freedom.  Four of his books have been purchased or optioned for the Big Screen.  In addition, John has written four screenplays for Hollywood, adapting the works of Nelson DeMille, Norman McLean and Thomas Harris.  He will co-produce the film adaptation of his book, Six Minutes to Freedom, which should begin filming in the spring of 2016 for a 2017 release.

A frequent speaker at literary events, John also teaches seminars on suspense writing techniques at a wide variety of venues, from local libraries to The Smithsonian Institution.  Outside of his writing life, John is a renowned safety expert with extensive knowledge of explosives, weapons systems, hazardous materials, and fire behavior.  John lives in Fairfax, VA.

LISTEN: http://www.blogtalkradio.com/suspensemagazine/2016/03/09/crime-and-science-radio-with-special-guest-bestselling-author-john-gilstrap

Link goes live Saturday 4-23-16 at 10 a.m. Pacific

LINKS:

John’s Website: http://www.johngilstrap.com

Weapons Resource: http://www.nssf.org/newsroom/writers/guide/ (a great 40,000-foot resource for writers who write about weapons)

Weapons Used in Movies: http://www.imfdb.org/index.php/Category:Movie (This site allows you to pull up a movie title and see all of the weapons used.)

 

Friendly Fire

NICK OF TIME MM (print) (1)

 

FORENSICS FOR DUMMIES Release Day

FFD 300X378

 

Forensics For Dummies Updated 2nd Edition is now available.

Get it through your local Indie Bookstore or here:

Amazon: http://www.amazon.com/Forensics-Dummies-Douglas-P-Lyle/dp/1119181658

B&N: http://www.barnesandnoble.com/w/forensics-for-dummies-douglas-p-lyle/1013991421

 

Forensics For Dummies, 2nd Edition Coming Soon

 

FFD 300X378

 

Just got the new cover for Forensics For Dummies, 2nd Edition.

It will be released from Wiley on 2-29-16

Pre-Order now

 

Fingerprinting Bullets: A New Forensic Science Technique

Bullets recovered from crime scenes or bodies can tell investigators a great deal: the caliber of the weapon can be determined by measuring and/or weighing the bullet; the marks left on the bullet’s surface by the lands and grooves and twists of the barrel can reveal the manufacturer; and these same striations can be used to match the bullet to a particular suspect weapon. These striations area the most individualizing and therefore the most useful in criminal investigations involving forearms.

But what if the bullet is too damaged for such comparisons? All is not lost. An analysis of the chemical make up of the bullet might reveal not only the manufacturer but also the batch from which it came. This might serve to narrow the location of purchase and ultimately lead to the perpetrator..

Bullet Fingerprints To Help Solve Crimes: http://phys.org/news/2014-07-bullet-fingerprints-crimes.html

 
 
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