Ithaca Gun Co. advertises a custom-made, lightweight, 28-gauge shotgun that's sure to titillate gun enthusiasts. Nearly 10 years after Cornell engineering students designed it, it's finally for sale.

Henry Asante, Faisal Mahmood, Chen-Tsuo Yen and Chris Tupino, all class of 2001, designed the shotgun for their master of engineering project. They did it entirely in ProEngineer, a computer-design software.

Ithaca Gun, an Ithaca fixture since 1880, ran into financial trouble soon after the students completed the design, and the company assets were sold in 2007. The students had graduated, and they assumed the gun would never actually get made.

Now based in Upper Sandusky, Ohio, Ithaca Gun recently informed John Callister, the students' faculty adviser, that their long-dormant designs were to become reality after all.

"The folks in Ohio called me and said they were hoping I still had the computer files on a disk," said Callister, senior lecturer in mechanical engineering and operations research.

All the parts, including the breech block, receiver, slide, carrier and trigger plate, were designed by the students. Dimensions and tolerances were specified to within four decimal places -- possible because of the students' precise calculations.

"It's heartening to see it's actually happening after all these years," said Tupino, an industrial engineer at Northrop Grumman Corp. in Baltimore. He says he keeps a copy of the design report in his desk at work to this day and still gets asked about the unusual project.

Callister said the project started because the company's marketing manager at the time wanted to expand the product line, but in a way that wouldn't disrupt manufacture of existing guns. That's where the students, whose majors ranged from operations research to mechanical engineering, came in.