Anheuser-Busch heir and former CEO Adolphus Busch IV has publicly resigned his life membership in the National Rifle Association, following the failure of popular gun legislation in the U.S. Senate this week.

BuschIn a two-page letter to the NRA released to St. Louis media (PDF), Busch, a hunter and outdoorsman, decried a "rigid new direction of the NRA," which he said "appears to have evolved into the lobby for gun and ammunition manufacturers rather than gun owners."

Busch, who guided Anheuser-Busch to its acquisition by InBev in 2008, questioned the NRA's lobbying against a gun bill that had wide support among the public and NRA members. "I fail to see how the NRA can disregard the overwhelming will of its members who see background checks as reasonable," wrote Busch, who also questioned why the group reversed its past position in favor of background checks.

Busch released his letter April 18.

"We disagree with his characterization, but we wish him all the best," NRA director of public affairs Andrew Arulanandam told the Huffington post.

Busch thanked NRA lobbyists Chris Cox and David Lehman for supporting environmental issues, but he said he felt compelled to act because of the "distorted values I see emerging within the NRA."

After a key amendment to the bill supporting expanded background checks for gun purchases was defeated in the Senate this week, Cox released a statement on behalf of the NRA calling the legislation "misguided." Cox said expanding background checks will not reduce violent crime or keep kids safe.