John Seim has spent at least a week at Trinidad State’s Summer Gunsmithing Series for more than 30 years. A couple of years ago he began documenting the tricky process of color case hardening, which was a common finish on guns in the 1800s. It involves heating a metal gun part and then quenching it cold water. Results can range from beautiful rainbows to disappointing blotchy grays or browns.

Seim, a retired medical doctor from Alberta, Canada, began experimenting with the variables in 2016, scientifically documenting the results from hundreds of experiments, mostly performed at Trinidad State’s Gunsmithing finishing lab. He wanted to demystify the technique and help people achieve more consistent results. He continued his experiments in the summer of 2017 and then began writing a book about the process. The book, Colour Case Hardening of Firearms, was vetted by Trinidad State Gunsmithing instructors and others and then went on sale through Amazon.

On July 19, Seim presented a check for $10,000 to Friends of Trinidad State, a group dedicated to supporting college gunsmithing efforts. “This represents the proceeds from the process of writing that book and distributing it. This is the money over and above costs,” Seim told his peers at a dinner gathering. Ever the student, Seim was back from Canada this summer to learn the art of scrimshaw. The week of July 23, while Seim was in an advanced scrimshaw class, the color case hardening class was going on three floors below. Trinidad State Gunsmithing Instructor Ryan Newport now uses Seim’s book as a class reference.

Chris Hanks, chairman of Friends of Trinidad State said, “John is really the latest in a long line of innovators who have worked here at Trinidad. P.O. Ackley started the program and was one of the great wildcatters of gunsmiths in the 40s and 50s, on to people like John Seim with many, many in between.”

The color case hardening process involves wrapping parts in a metal “cages” and then heating them to 1100 degrees. The parts are quickly quenched it in cold water. But minor variations can have a big effect on the look of the final product. Impurities in the water, a change in water temperature and even weather conditions can alter the outcome.

“There’s a lot of stuff out there (about color case hardening), but it’s never been collated. There’s also a lot of gaps in knowledge. This is really a science,” said Seim. “It’s not a witchcraft sort of exercise. I have a background in science, so it was second nature for me to do some experimentation, with some assistance from a number of people like Keith Gipson who reviewed the book to make sure the manuscript was accurate both scientifically and technically. And the book came together.”

Seim has sold 370 books and is working on a second edition. He believes he may sell a thousand.