The Marine Corps' top general said a force-wide review that could close some military occupational specialties and beef up others could be completed by the end of the year.

Marine leaders are running simulations on different models of the Corps as part of a months-long effort to redesign the force. Commandant Gen. David Berger announced the need for a force structure review in planning guidance he released shortly after becoming the service's top general.

Now, leaders are closing in on the end of that review, Berger told Military.com this week.

"I'm hopeful in another 30 to 45 days," he said. "But this is of such significance that we can't rush to an answer. It's got to be right. We're not going to get a second chance."

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Berger has declined to discuss MOSs that could get the ax as part of the force structure review. But this week, he hinted at the potential for serious shake-ups.

"The Marine Corps we're going to will look very radically different than what we have right now," he said at an event hosted by Johns Hopkins University's School of Advanced International Studies in Washington. "And that's going to not be easy, fiscally or emotionally."

Marines are organized to fight another Gulf War, the commandant re-emphasized, but they're not set up to defeat a superpower.

"We are designed ... for a competition behind us, not in front of us," he added. "And that's driving the Marine Corps to redesign our force."

He told reporters last month that some of the changes could be driven by technology advancements. This week, Berger added that one of the more challenging parts of the force structure review will be getting rid of equipment the Marine Corps has relied on for decades.

"I think convincing our leaders and our alumni, retired Marines, that we have to get rid of [some things] because we're going to need some of that new stuff, because we're going to operate as a naval force, is the shift we must make," he said.

Berger wrote in his planning guidance that force design would be his No. 1 priority. He also told Military.com this summer that he's prepared to consider a smaller service to pay for upgrades in other areas.

-- Gina Harkins can be reached at gina.harkins@military.com. Follow her on Twitter @ginaaharkins.

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