Shutting down the government over Obamacare hurt Republicans and gained nothing, billionaire Home Depot founder Ken Langone told CNBC on Wednesday.
Describing himself as a "loyal, enthusiastic Republican," Langone took to task House Republican Policy Committee Chairman James Lankford of Oklahoma during a "Squawk Box" interview.
"Congressman, help me out," Langone said. "What the hell did you guys gain by shutting the government down other than to get a black eye for all of us?"
Lankford, also a Budget Committee member, responded, "I would agree. We got a black eye on it. The problem that we have is we overreached."
(Read more: Obamacare can't make health care cheaper: Langone)
The government shutdown began Oct. 1—coincidentally, the same day the federal Obamacare exchange opened for Americans to enroll for health coverage or face a tax penalty for not signing up by early 2014. The partial closure of federal operations ended after 16 days with temporary deals to fund the government until Jan. 15 and extend the debt ceiling until Feb. 7.
"At the ending of the negotiations before the government shutdown, our last offer was just delay the [individual mandate] penalty for a year," Lankford said. President Barack Obama "shut down the government and went back to our previous statement and said, 'This is what they are holding out for.' No one heard what our last [Obamacare] offer was."
Lankford then argued that both Republicans and many Democrats now agree the health-care law isn't ready, adding, "That's where we were before the shutdown."
(Read more: Governor to Obamacare critics: 'Chill out')
Earlier in the show, Langone said, "What I would have done if I was a Republican in Congress … I'd have let [Obamacare] happen."
While against the law, he said, he would have advocated a strategy of letting the law roll out to highlight the problems.
"Ironically, the government reopens and a few days later we find out we can't run this thing," he said.
—By CNBC's Matthew J. Belvedere. Follow him on Twitter @Matt_SquawkCNBC.