While Warner Bros.’ “Gravity” may not hit stratospheric heights this weekend at the box office, the 3D space epic starring Sandra Bullock and George Clooney is displaying exceptional pull with audiences in 3D, with tracking suggesting a $40 million-plus Stateside opening.

According to online ticketing site Fandango, “Gravity” is on track to score record 3D pre-sales, outpacing “Avatar” with 91% of tickets sold in stereo. That’s especially significant since 3D has been on such a downslide lately.

A $40 million-plus bow for “Gravity” would be one of the largest openings in October. “Paranormal Activity 3” currently holds the record for the largest launch during this month with $52 million.

Aside from “Gravity,” Fox launches Ben Affleck-Justin Timberlake action pic “Runner Runner,” which is expected to gross a modest $10 million-$12 million in wide release. The $30 million-budgeted film, from helmer Brad Furman, opened last weekend overseas and has grossed more than $12 million from 43 markets so far.

Meanwhile, Sony is sneaking Paul Greengrass’ Tom Hanks starrer “Captain Phillips” at north of 800 domestic locations on Saturday. The previews are aimed at building word of mouth for the ripped-from-the-headlines Somali pirate movie, which bows wide next weekend.

“Gravity” and “Captain Phillips,” both squarely in the awards discussion, are bowing during a time when distributors have successfully launched such adult-targeted dramas as “Argo,” “The Town” and “The Departed,” all of which had fairly modest openings but went on to have strong awards-fueled legs.

“This time of year it’s really difficult to break out of the $30 millions,” said Warner domestic distribution prexy Dan Fellman. “That means on Friday the picture has to do, at least, $15 million.”

The higher bar for “Gravity” is entirely feasible, with the film’s new technology developed by director Alfonso Cuaron and 3D presentation driving buzz among fanboys and first-responders, who should boost opening-night box office.

Reviews for “Gravity” have been almost unanimously glowing, with a 98% rating on Rotten Tomatoes. “Runner Runner,” on the other hand, has a dismal 13% appraisal.

At the specialty box office, Bob Berney’s newly revived Picturehouse is expanding “Metallica Through the Never” to 650 locations after the pic’s solid debut last weekend, earning $1.7 million from 305 Imax theaters.

A few other films are getting more aggressive bows, such as Roadside Attractions’ music drama “Grace Unplugged,” at 511 playdates, and Pantelion’s Spanish-English language film “Pulling Strings,” which bows Friday at 387 locations. Also, Exclusive Media launches JFK drama “Parkland” at 217.