Los Angeles ? “The Dark Knight” continues to obliterate box office records, crossing the $300 million mark in just 10 days.

The epic Batman saga grossed $75.6 million in its second weekend in theaters, pushing its domestic total to $314,245,000, Warner Bros. head of distribution Dan Fellman said Sunday.

That surpasses the record set in 2006 by “Pirates of the Caribbean: Dead Man’s Chest,” which took 16 days to make $300 million.

The latest Batman installment already had broken records for best opening weekend at $158.4 million and best single-day with $66.4 million. It’s also busted records in its showings on IMAX screens, making $16.3 million in its first 10 days.

Fellman expects that “Dark Knight” could reach $400 million in about 18 days, which would beat the record that “Shrek 2” set in 2004 when it made that much money in 43 days.

Part of the film’s visual allure comes from the fact that 30 minutes of it were shot with IMAX cameras, including an elaborate bank-heist scene at the start. “Chris (Nolan) has clearly hit upon something,” said Greg Foster, chairman and president of IMAX Filmed Entertainment.

“There are many important filmmakers who we’ve spoken with in the last couple of weeks about shooting with IMAX cameras.”

“The Dark Knight” could pass “Titanic” as the highest-grossing film in U.S. history, said Paul Dergarabedian, president of Media By Numbers. James Cameron’s 1997 extravaganza made $600,788,188 domestically, a record no other movie has come close to touching.

Coming in second place was “Step Brothers,” which had a strong opening of its own with $30 million. The Sony comedy reunites Will Ferrell and John C. Reilly, co-stars of “Talladega Nights: The Ballad of Ricky Bobby,” as 40-year-olds who’ve never left home and are forced to share a bedroom when their parents get married.

Sony also has the Will Smith superhero flick “Hancock,” which made $8.2 million over the weekend to cross the $200 million mark.

The weekend’s other big release was “The X-Files: I Want to Believe,” which made an estimated $10.2 million. Ten years after the first “X-Files” movie and six years since the pioneering sci-fi show went off the air, this latest installment finds Mulder (David Duchovny) and Scully (Gillian Anderson) reteaming to solve a missing-persons case.

“The hardcore ‘X-Files’ fans, they’re happy. And frankly, that’s who the movie was made for,” said Chris Aronson, distribution executive for 20th Century Fox.

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters, according to Media By Numbers LLC:

1. “The Dark Knight,” $75.63 million.

2. “Step Brothers,” $30 million.

3. “Mamma Mia!” $17.9 million.

4. “The X-Files: I Want to Believe,” $10.2 million.

5. “Journey to the Center of the Earth,” $9.4 million.

6. “Hancock,” $8.2 million.

7. “WALL-E,” $6.3 million.

8. “Hellboy II: The Golden Army,” $4.9 million.

9. “Space Chimps,” $4.4 million.

10. “Wanted,” $2.7 million.