Thomas,
Thank you very much for your generous comments.
I decided to become a professional writer at about age 12, about the same time my father gave me my first rifle (I'd already been a dedicated angler and BB-gun shooter for several years). My father and mother were both professors who kept thousands of books in the house, including a good encyclopedia, and from the time I could read encouraged me to use them for research. Right outside was outdoor Montana, which in those days had around 700,000 people in an area slightly smaller than California.
I sold my first magazine story at 21 to Sports Illustrated, about a day of flyfishing for trout in winter, which paid me more than I made in a month at my regular job. Back then there was still a considerable market for stories, rather than articles, even in hunting/fishing magazines. I was able to make a living writing by my late 20's, writing a LOT of different stuff, from hunting and fishing stories to fiction and Western history, including an article for National Geographic on the Missouri Breaks. All this provided a well-rounded writing background, and in college I majored in biology, providing some science background.
I started gun writing in my mid-30's, another subject I was interested in, and various magazine editors wanted more. Eventually gun writing became the biggest part of my income, but still write some other stuff, though I gave up fishing writing 20 years ago.
The other thing my parents provided was a certain skepticism about "common knowledge," the stuff many people believe is true because they heard it from somebody else. Shooters have plenty of these misconceptions, and I've published a lot of articles based on investigating some of those beliefs. Luckily, many people in the shooting business are willing to share their expertise on everything from ballistics to making reloading components. Also, Elmer Keith once expressed his belief in doing sufficient shooting to be sure of what he published. I've found that a good rule, on subjects from handloading techniques to how hunting bullets work. I also have a library on hunting and shooting that's probably the size of my parent's collection, providing background info going back to the 19th century.
I combine all those elements when writing articles. Usually the biggest problem is distilling any subject into 2000-2500 words, but have found it really helps to take the reader along while doing my investigating, instead of merely listing the results One of oldest of effective writing techniques, both in fiction and non-fiction, is showing instead of telling.
