After attempting an allegorically profound orgy of violence in his adaptation of J.G. Ballard’s “High-Rise”—to disastrous effect—writer-director Ben Wheatley jettisons subtext completely in “Free Fire,” another movie with a high blood quotient and body count but one that has nothing whatever on its mind besides visceral thrills. While giving Wheatley the chance to exhibit his technical skill and the cast the opportunity to have fun schlocking it up, it aims so low that it winds up seeming like a movie made for viewers with a hankering for the sort of mindless junk they used to watch from their cars at drive-ins.

The plot, such as it is, could be written on a random piece of scrap paper. Sometime during the seventies—all the better to feature the era’s outlandish outfits and hair styles (as well as to explain the absence of cell phones, which would ruin the entire premise)—the picture is little more than a ninety-minute shootout between two gangs of thugs, one a group of gun-runners and another of prospective IRA buyers, in an abandoned warehouse. The former include partners Vernon (Sharlto Copley) and Martin (Babou Ceesay), along with their “muscle” Gordon (Noah Taylor) and Harry (Jack Reynor), while the latter are headed by Chris (Cillian Murphy), seconded by Frank (Michael Smiley) and his goofy sidekicks Stevo (Sam Riley) and Bernie (Enzo Cilenti). The go-betweens are smooth, smart-ass Ord (Armie Hammer) and cool beauty Justine (Brie Larson).

There is some initial haggling between Vernon, a slimy, snide sort of guy, and Chris, more intensely businesslike, over the quality of the arms—the guns aren’t the model previously agreed on. But the atmosphere remains non-violent until a coincidence sets off sparks. By chance the doped-up Stevo had gotten into a fight the previous night with Harry over his treatment of one of Harry’s female relatives, and the two men come to blows, with shots eventually being fired at roughly the picture’s thirty minute mark. Before long everybody seems to be shooting at everybody else while firing quips at one another in the quiet between the salvos. They also take turns trying to get their hands on a case containing the cash Chris brought along to pay for the guns.

While the two groups take (mostly poor) aim at one another, winging various participants repeatedly but rarely making a kill shot, the party is interrupted by the appearance of two anonymous snipers in the rafters, who target both groups pretty indiscriminately. That adds another aspect to the carnage, and also raises the question of whom they’re in league with—after all, they must have been hired by somebody who knew in advance about the meeting. That increases the level of distrust—and violence—on the floor.

The mayhem goes on for the remainder of the picture—an hour or so of people trading gunfire, scrambling about in the dust, tussling when they collide, setting gasoline ablaze, and trying to make their way to the run-down van that might carry them off the shooting range. It’s eventually revealed which of them hired the snipers, and another IRA man arrives on the scene only to become involved in the action himself, but everything inevitably ends with the final survivors whittled down to one.

Wheatley’s inspiration in all this is clearly Quentin Tarantino, and particularly early Tarantino, prior to the American’s embrace of large-scale panoramas and topics like slavery and war, even if he might treat them with an ironic tone. But the Brit doesn’t have his model’s gift of gab; the banter flung to and fro by the shooters rarely rises above the juvenile, never achieving the almost poetic riotousness of Tarantino’s best monologues. Nor does he choreograph the action with much elan, or keep it from developing a decidedly repetitive feel. By the end even action fans might be getting bored, although Wheatley adds a few gored-up moments to increase the shock quotient.

In the circumstances the actors can’t do much but strike the necessary poses. The most successful are Copley, who practically oozes sleaze, and Hammer, who exudes slick smarminess. Riley, Raynor and Cilenti do their wacked-out shtick with abandon, but the others, including major names Murphy and Larson, are surprisingly colorless, though Ceesay gets one memorable moment as a man back from the dead. On the technical side, the movie is pretty ordinary, with Laurie Rose’s cinematography as murky as one might expect in a lower-tier horror movie and a score by Ben Salisbury and Geoff Barrow that strives strenuously to up the energy, though without much effect.

Ultimately Wheatley’s empty exercise in spoofy carnage can’t sustain itself over feature length. It will appeal to those who found “Grindhouse” a rare treat, but there weren’t many of them.