In a business that is booming with geographic expansion and product innovation, Billy Busch is focused on the tried and true: selling a classic American lager in St. Louis.

One year in, he’s finding a niche.

Busch says his Kräftig Lager and Kräftig Light are winning about 1 percent of beer sales in the St. Louis market, a year after the brews launched to much fanfare.

To celebrate — and to keep growing — William K. Busch Brewing plans to roll out 30-packs of Kräftig next month, in a bid to tap more volume in supermarket sales.

“Consumers have been asking for it,” said William Schierman, the company’s chief sales and marketing officer. They also plan to beef up marketing, particularly through radio and social media.

“We’re looking to grow,” Busch said.

It’s the latest in a series of measured steps Busch has taken over the past few months to develop the fledgling brewery. He opened about a year ago, hoping to capitalize on his famous last name here in St. Louis and pry loose mainstream beer drinkers from bigger rivals, then build quickly into a national player. New markets have come slower than first expected, but Busch said sales were going better than projected.

“I think the story of our company has been resonating with customers,” Busch said. “And people in St. Louis know a good beer.”

There have been a few bumps along the road. The brewer’s initial chief executive — Anheuser-Busch veteran Jim Hoffmeister — left the company shortly after Kräftig’s launch.

A former marketing consultant sued Busch last fall claiming Busch still owed him $650,000. That suit was resolved in August, an attorney in the case said. A second lawsuit, filed in June by a brewing consultant for about $83,000, is still pending in St. Louis County Circuit Court.

It’s hard to tell exactly how sales are going — the private company doesn’t share its sales figures.

But trade publication Beer Marketer’s Insights, citing data from the Missouri Beer Wholesalers Association, reported earlier this month that William K. Busch had shipped about 8,000 barrels in the first nine months of the year in Missouri (Kräftig is also on shelves in the Metro East and Springfield, Ill.). It had sold about 5,900 as of June 30.

That would put Busch on pace to sell about 10,700 barrels in Missouri for the year. For comparison’s sake, that’s about one-third of the volume sold by Schlafly parent The St. Louis Brewery — the largest independent brewery based in St. Louis — in the 12 months ending June 30, according to state figures. O’Fallon Brewery recently said it’s on pace to sell about 11,500 barrels this year.

Unlike those breweries, which offer a variety of flavors and salvos of seasonal brews, William K. Busch focuses on one product: a classic American light lager.

That prevents diluting the brand, said Busch, and reinforces Kräftig’s connection with quality — Busch makes no secret that his brew adheres to Reinheitsgebot, the five-century old German purity laws.

It also, however, puts the company squarely in a slice of the beer business — so-called “premium lagers” — that has been losing customers as drinkers migrate to more flavorful craft beers and malt beverages.

Sales of Budweiser — the major beer that’s perhaps closest in style to Kräftig — have slumped for two decades straight. Bud Light and Miller Light are down too in recent years.

That said, as Busch points out, many people still drink premium lagers. The category includes the four biggest-selling beers in the U.S. — Bud Light, Coors Light, Budweiser and Miller Lite — and they combined to make up 43 percent of all sales last year, according to Beer Marketer’s Insights. Busch sees room for Kräftig to pick off some of those customers.

“That’s where the business is,” he said. “It’s still a big pie.”

The other thing Busch is not doing is adding new markets, at least for now.

When they launched a year ago, Busch and his partners talked openly of quick growth across Missouri and Illinois. And while they rolled out in Springfield, Ill., in February, those plans have been pared back, at least for now. The main priority, Busch said, is growing market share in St. Louis. After that they will gradually add adjacent markets such as central Missouri or other parts of downstate Illinois.

“Once we build a solid foundation in St. Louis, we’ll start looking to go broader,” Busch said. “Right now we’re a local company. We plan on becoming a regional company. Ultimately we want to be a national company.”

National has always been the stated goal for Kräftig. A year ago, Busch’s team was talking about 2 million barrels a year, which would make them roughly the size of Sam Adams parent Boston Beer Co. To get there, Busch will have to achieve another long-stated — but still distant — goal: a brewery in St. Louis. Right now, the company brews its beer under contract in LaCrosse, Wis., trucking the green-and-black bottles eight hours to get here. Busch would like to make his product in his hometown, and says he’s “moving down the road” toward that.

“When it’s going to happen, we can’t say for sure,” he said.

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