Though he lives not far from his boyhood home in Maple Plain, Minn., Knapp has come a long way in his 56 years.
His sponsor list reads like a who's who of international shotgunning, and includes Twin Cities-based Federal Cartridge Co. And he travels the world giving shooting demonstrations for Benelli.
"I just returned from Italy and Bulgaria," he said.
Knapp holds three world shooting records. One, set in 2000 when he tossed eight clay targets into the air and broke them individually, was accomplished with a pump shotgun. The other, involving the 10 broken clays, was completed with a semi-auto scattergun.
But Knapp wasn't always "A Shooting Star," as he is now billed.
For 25 years, he worked for Hennepin County Parks, mostly in maintenance, all the while nursing his shooting dreams.
Back then, the cost of pushing as many as 150,000 rounds a year through his shotgun, some for practice, some for show, was his alone to pay.
"I traveled around, giving un-sponsored shooting shows for seven years," he said. "Those were pretty hard times, financially."
But Knapp had just enough of Parsons-the-showman in him to figure out that the media -- TV in particular -- could help him get where he wanted to go.
"I had a lot of TV guys come out to film me, some of them reluctantly at first," he said. "I remember Tom Ryther, the sportscaster, came out quite a few years ago. I broke clays in the air, vegetables, everything. Then, at the very end, I shot a gallon of gas I had rigged with a detonator. That got him excited."
On the road, Knapp often called a local TV station to tell them "you might want to send a cameraman" to his show.
When he had amassed enough video clips, Knapp packaged them for potential sponsors.
He caught a break in 1989 when Federal said it would supply him with shotgun shells. In 1991, Winchester offered the same booty, plus a little cash.
Knapp rode a bigger updraft still a couple of years later, when Benelli took him on. And he's now back with Federal.
These days, he travels nearly every weekend, leaving from Minneapolis-St. Paul International Airport on Friday mornings, or sometimes Thursday nights, flying to California, New York, and everywhere in between.
Accompanying him are four shotguns, a patch-laden shooting vest, a pair of amber shooting glasses, special hearing protection -- and a knack for busting clay targets.