Microstamping Guns Feasible but Flawed, Study Finds

Since I grad­u­ated from UC Davis, and per­son­ally know some­one involved in the research per­formed in this study, I think it’s impor­tant for peo­ple to know what sci­en­tists have found while look­ing at the fea­si­bil­ity of this technology.

While I make no per­sonal com­ment on the tech­nol­ogy since I have no first hand test­ing expe­ri­ence, I think this is impor­tant infor­ma­tion, and would hate for it to be lost as some reports seem to do.

It was orig­i­nally located here.

May 3, 2007

Note: A cor­rected ver­sion of this press release was pub­lished May 15.

New tech­nol­ogy to link car­tridge cases to guns by engrav­ing micro­scopic codes on the fir­ing pin is fea­si­ble, but does not work well for all guns and ammu­ni­tion tested in a pilot study by researchers from the foren­sic sci­ence pro­gram at UC Davis. More test­ing in a wider range of firearms is needed to deter­mine the costs and fea­si­bil­ity of a statewide pro­gram of micro­stamp­ing, as called for by pro­posed state leg­is­la­tion, the researchers said.

The tech­nol­ogy devel­oped by ID Dynamics of Londonderry, N.H., uses a laser to cut a pat­tern or code into the head of a fir­ing pin. The method is sim­i­lar to that used to engrave codes on com­puter chips. When the trig­ger is pulled, the fir­ing pin hits the car­tridge case or primer and stamps the code onto it. In prin­ci­ple, the spent car­tridge can then be matched to a spe­cific gun.

If suc­cess­fully imple­mented, micro­stamp­ing would be one addi­tional piece of evi­dence for inves­ti­ga­tors to gather in build­ing a crim­i­nal case, said Fred Tulleners, direc­tor of the foren­sics pro­gram at UC Davis. Tulleners was for­merly direc­tor of the California Department of Justice crime lab in Sacramento, as well as the Sacramento and Santa Rosa county crime labs.

UC Davis grad­u­ate stu­dent Michael Beddow tested fir­ing pins from six dif­fer­ent brands of semi-automatic hand­guns, two semi-automatic rifles and a shot­gun. The fir­ing pins were engraved with three dif­fer­ent types of code: a letter/number code on the face of the fir­ing pin; a pat­tern of dots or gears around the pin; and a radial bar code down the side of the pin.

To test the effects of repeated fir­ing, Beddow fit­ted engraved fir­ing pins into six Smith and Wesson .40-caliber hand­guns that were issued to California Highway Patrol cadets for use in weapons train­ing. After fir­ing about 2,500 rounds, the letter/number codes on the face of the fir­ing pins were still leg­i­ble with some signs of wear. But the bar codes and dot codes around the edge of the pins were badly worn.

“They were ham­mered flat,” Beddow said.

Tests on other guns, includ­ing .22, .380 and .40-caliber hand­guns, two semi-automatic rifles and a pump-action shot­gun, showed a wide range of results depend­ing on the weapon, the ammu­ni­tion used and the type of code exam­ined, Beddow found. Generally, the letter/number codes on the face of the fir­ing pin and the gear codes trans­ferred well to car­tridge cases, but the bar codes on the sides of the fir­ing pin per­formed more poorly. Microstamping worked par­tic­u­larly poorly for the one rim­fire hand­gun tested.

The researchers did not have access to infor­ma­tion allow­ing them to read the bar– or gear-codes, and so could not deter­mine if these remained leg­i­ble enough to be useful.

Codes engraved on the face of the fir­ing pin could eas­ily be removed with house­hold tools, Beddow found.

The researchers esti­mated that set­ting up a facil­ity to engrave the fir­ing pins of every hand­gun sold in California would cost about $8 per fir­ing pin in the first year, falling to under $2 per fir­ing pin in sub­se­quent years, Tulleners said.

Tulleners said that a larger test of about 3,000 fir­ing pins, from a wider range of guns, would allow for a more “real-world” test of the tech­nol­ogy. About 650 brands of hand­guns are sold in California, com­pared with the nine tested, Beddow esti­mated in the study. A big­ger study would also help show how use­ful this tech­nol­ogy might be in detect­ing and pre­vent­ing crime.

The study was com­mis­sioned by the California Policy Research Center at the request of the California Legislature.

“We want to make sure that the leg­is­la­ture has good infor­ma­tion if they are going to make deci­sions about this,” Tulleners said.

David Howitt, pro­fes­sor of chem­i­cal engi­neer­ing and mate­ri­als sci­ence and chair of the Graduate Group in Forensic Science at UC Davis, super­vised the project. Howitt said that while the tech­nique tested here has lim­i­ta­tions, there are other pos­si­ble ways to imple­ment micro­stamp­ing. For exam­ple, an ultra-hard ceramic that would be extremely dif­fi­cult to file off could be used to make the impres­sion, instead of the rel­a­tively soft fir­ing pin.

More uni­ver­sity involve­ment is needed to address these sorts of foren­sic sci­ence issues from their incep­tion, Howitt said.

UC Davis offers a master’s degree in foren­sic sci­ence through UC Davis Extension. Courses are taught by an inter­dis­ci­pli­nary group of UC Davis fac­ulty and out­side experts. The pro­gram cur­rently has an enroll­ment of about 60 stu­dents.
Media contact(s):

* Michael Beddow, Forensic Science Graduate Program, (928) 607‑4555, mtbeddow@ucdavis.edu
* Fred Tulleners, Forensic Science Graduate Program, (530) 757‑8699, ftulleners@ucdavis.edu
* Andy Fell, UC Davis News Service, (530) 752‑4533, ahfell@ucdavis.edu