Sen. Joe Manchin, D-W.Va., a lifelong member of the National Rifle Association, said Monday it's time to discuss gun policy and move toward action on gun regulation following the school shooting in Connecticut that killed 20 children.

The conservative West Virginia Democrat said Monday on MSNBC's "Morning Joe" that he is a "proud outdoorsman and hunter, but this doesn't make sense."

He is the most prominent gun rights advocate to speak publicly in the wake of the shooting.

"I ask all my friends at the NRA," said Manchin. "We need to sit down and move this dialogue to a sensible and reasonable approach to fixing it. It's part of it but not all of it. But everything needs to be on the table,and I think it will be.

Manchin specifically mentioned bringing stakeholders, including the NRA, into discussions with his colleagues in the U.S. Senate. Sen. Dianne Feinstein, D-Calif, is vowing to reinstate the federal assault weapons ban, Sen. Charles Schumer, D-N.Y., has called for limiting the number of rounds allowable in an ammunition clip, and Sen. Joe Lieberman, I-Conn,has called for the formation of a "blue ribbon" commission to study all possible facets of the tragedy, including weapons, mental health and violence in music, films, television and video games.

"This is bigger than just about the guns," said Manchin. "This is about how we treat people with mental illness. How we intervene. How we give them the care they need. How we protect our schools."

Manchin drew attention in 2010 with a campaign ad called "Dead Aim" in which he fired a single bullet from a hunting rifle through a piece of paper representing the cap-and-tradeenvironmental bill.

Manchin said during a telephone conference call Monday that he had no regrets about the ad and said that it shows responsible gun use.

"I don't know anyone in the sporting or hunting arena that goes out with an assault rifle," said Manchin. "I don't know anybody who needs 30 rounds in the clip to go hunting."

Manchin, who has earned an A rating from the National Rifle Association, said contrary to other reports, he is not in lock-step with New York City Mayor Michael Bloomberg who, like Feinstein, wants to reinstate the assault weapons ban.

However, Manchin said he's "not afraid to talk about it."