The raising is priced at 22c per share, with the stock generally trading this year in the 25-28c range, up from levels around 7-8c 12 months ago.
Silver Mines says Bowdens has "outstanding support locally", with the development set to cost $250 million to bring into production and be capable of generating earnings (EBITDA) averaging $116.5 million per annum in the first three years.
Bowdens has a post-tax net present value of $192 million and internal rate of return of 24%.
The modelled 16.5-year project will produce a total of 53Moz of silver, 108,000t of zinc and 79,300t of lead, with all-in sustaining costs for the silver put at $17.53/oz.
Silver Mines is currently drilling high-grade prospects at Bowdens, and awaiting drill assays from a gold exploration project within an historical gold field near the town of Blayney.
The company started the year with about $3.6 million cash and has about $7 million in options expiring later this year that are ‘well-in-the-money'.
Shares in Silver MInes were down 9% to 25c in morning trade, capitalising the company at $260 million.