The new money has been provided by venture capital group Causeway and banks led by NM Rothschild to support further expansion of Mill House's theme family pubs - to 30 outlets over the next year.
The group, which was only set up in April 1995, is the latest to capitalise on fast growth among independent operators in the booming family pub and restaurant market as the big brewers and pub groups shed chunks of their massive estates.
Only last week, Tom Cobleigh founder Derek Mapp became the latest in a series of new pub multi-millionaires to sell out in a pounds 96m deal with leisure giant Rank. He founded the 44-strong chain with one pub five years ago and came to market in a pounds 60m flotation less than a year ago.
As GrandMet's property chief, Mr Williams played a lead role in restructuring the group's 8,450-strong Inntrepreneur pub joint venture with Fosters, most of which has now been sold.
Mr Williams started Mill House with 12 pubs sold off by Phoenix Inns, which bought a large slice of the Inntrepreneur estate a year ago last January.
With finance director Chris Parratt, who did the same job at GrandMet Estates, and former Taylor Walker managing director David Longbottom, he has built the chain up to 19 pubs.
Annual turnover is currently running at just under pounds 10m, but the target is pounds 30m - pounds 1m per pub - by the time the firm has the necessary three-year track record for a main market listing.
"The one thing the sites lacked was that they had no money spent on them for years. Our secret is good design, bringing in children and families, but not putting off the guy who also wants to have a beer with his mates," Mr Williams said.