Phoenix PD Ruger P-95 LEA scans

2020-02-03T17:18:31Z (GMT) by Susan Vanderplas Heike Hofmann
Email csafe@iastate.edu to obtain the data.

The data consist of scans of bullet land engraved areas in x3p format. The study is structured so that there are 8 barrels (identified with an alphanumeric code, such as A9, C8, etc.) used to fire the known bullets in the study, with three bullets known to be fired from each barrel (Bullet1, Bullet2, Bullet3). Each bullet contains 6 land engraved areas, which are identified as Land 1-Land 6.

In addition to the 24 bullets with known provenance, there are 8 "unknown" bullets which can be matched to the 8 barrels, for a total of 32 bullets. Each bullet has 6 land engraved areas, for a total of 192 scans. Unknown bullets are identified with a letter.

This study is an open study, that is, not all of the unknown bullets may match to the known barrels in the set. Some of the unknown bullets may have been fired from other types of Ruger handguns.

The x3p format provides for the inclusion of relevant metadata within the x3p file, including the machine used to scan the bullets, the operator, and the resolution of the scan. The total dataset size is about 3.4 GB.

Files are grouped as follows: BarrelXX/BulletY/ with the land number identified as part of the filename.

Information on x3p format: https://www.iso.org/standard/62310.html

We have produced two R packages meant to work with this data:
- x3ptools (on CRAN, with dev versions on github at heike/x3ptools). x3ptools contains utilities for reading, writing, annotating, rendering, and exporting x3p data to other formats.
- bulletxtrctr (dev version on github at heike/bulletxtrctr). bulletxtrctr contains utilities for extracting useful data from bullet LEA scans as well as a matching algorithm used to match unknown bullets to the barrels they were fired from.

Scans were created by Bill Henderson at Sensofar. Tylor Klep of the Phoenix Police Department designed the study and collected the bullets.