(Adds new recommendations by proxy adviser Glass Lewis)

By Ross Kerber

BOSTON, Sept 6 (Reuters) - The parent company of gunmaker Smith & Wesson on Thursday defended its directors and its contribution disclosures ahead of a proxy vote that will test how far leading fund firms will press concerns about firearms safety, and won rare new recommendations from a proxy adviser.

In a filing with the U.S. Securities and Exchange Commission, American Outdoor Brands Corp responded to proxy adviser Glass, Lewis & Co, which on Tuesday had recommended investors withhold their support from half of the company's 10 board nominees and backed a call for a safety report.

In an unusual update, a spokesman for Glass Lewis on Thursday evening sent a new version of its report stating that in light of American Outdoor's additional disclosures, it would recommend against only one director nominee. The proxy adviser still backed the call for the safety report.

The new view underscores the attention being focused on American Outdoor's Sept. 25 shareholder meeting, which will likely spotlight just what role the financial industry should play overseeing firearms companies.

After a gunman wielding a Smith & Wesson assault-style rifle massacred 17 people at a Florida high school in February, some banks restricted firearms lending, and asset managers including BlackRock Inc and Vanguard Group said they would speak to gunmakers about the safety of their products.

BlackRock and Vanguard, which together hold about 20 percent of American Outdoor's shares, must decide how to vote at the shareholder event, to be held only online.

In recommending votes be withheld from director Mitchell Saltz, Glass Lewis' new report cited how the company had not disclosed that he also sits on the board of police training services provider VirTra Inc, a potential conflict of interest.

Glass Lewis initially had recommended votes against four other directors over the issue, but changed its stance in light of American Outdoor's disclosure Thursday that the lack of disclosure was due to "an inadvertent omission" by Saltz.

The company's filing also reiterated arguments the safety report is unnecessary, saying among other things that the smart gun technology proponents would like reviewed "is not commercially viable or reliable."

American Outdoor also said its policy did not require it to disclose contributions of $1.5 million it has made to groups including the National Rifle Association, the politically influential gun rights advocate.

The proxy adviser previously noted criticism by a shareholder activist group, Majority Action, that the company should have reported the money. In its update Glass Lewis said while shareholders should not vote against directors only on the issue, they should "take note" given past rocky relations between the company and the NRA.