"Full Metal Jacket" may have provoked more strong and diametrically opposed opinions than any film since "Blue Velvet" -- everything from "superbly made" to "this didactic, static harangue." And that's just the prerelease reviews. But it also looks like just one more in the steady stream of post-"Platoon" Vietnam movies.

This week, principal photography began on "Bat 21," a Vietnam drama starring Gene Hackman and Danny Glover and directed by Peter Markle. And an older Vietnam picture also will be making its way from the video stores back onto movie screens: This week the Los Angeles Times disclosed that a rerelease is in the works for "Apocalypse Now," the 1979 Francis Coppola epic. The overlooked 1978 Vietnam film "Go Tell the Spartans" is also being reissued this year.

"Apocalypse" writer-turned-director John Milius, meanwhile, also told the Times that his next film, "Farewell to the King," will star Nick Nolte as a shipwrecked British soldier who leads a tribe of headhunters. Nolte will have an eye-catching costume, said Milius: He'll carry a Thompson submachine gun and wear either a sarong or a loincloth.

'Project X' and Chimp Rights "Project X" is prompting a lot more talk now than it did during its brief, lackluster run. But the current controversy has to do with the treatment of the chimpanzees used in the Matthew Broderick adventure film: After rumors began to spread about the mistreatment of the chimps used in the movie, a special-effects man on the film said he saw the apes beaten with fists and blackjacks. The American Humane Association, however, said it couldn't find any evidence of mistreatment, and two "Project X" trainers admitted that the chimps were occasionally spanked, but strongly denied that anything rougher took place.

Summer's Boffo Box Office "Predator" dropped by about a third between its first and second weekend, which is actually a pretty good showing for an action film. But "The Witches of Eastwick" fell by only 13 percent, which is a good showing for any film, and that's why "Witches" became the country's biggest-grossing film the same weekend that Jack Nicholson's beloved Lakers won the national basketball championship.

And though the competition gets tougher with "Spaceballs," "Full Metal Jacket" and "Dragnet" opening this week, last week was heartening -- and unusual -- in that virtually all the movies on the top box office list had reason to be optimistic. "Beverly Hills Cop II" and especially "The Untouchables" still have solidly respectable per-screen averages, and the former only dropped 14 percent while the latter increased its weekend total by adding 500 more screens. "Roxanne" trailed only "Witches" in its per-screen average, suggesting that Columbia Pictures was right to cut back the scope of its release and hope for good word-of-mouth advertising. "Harry and the Hendersons" is holding up well, and "Benji the Hunted" could have done better but is more than respectable for a film that stars a dog and contains virtually no dialogue. In fact, you have to move to the No. 8 film on the list, "The Believers," before you run into a picture that's clearly and unequivocally on its way down.

"Beverly Hills Cop II," incidentally, passed the $100 million mark in box office grosses in its 29th day in the theaters. That's the third-fastest $100 million in history, topped only by "Return of the Jedi" (23 days) and "Indiana Jones and the Temple of Doom" (25 days).

The Run for the Record Amid all the talk about how this year's box office grosses are potential record-breakers, here's one less optimistic prediction: The Hollywood Reporter has compared and analyzed figures for the past few years, and concluded that this summer's business, good as it has been, needs a significant boost to equal the summer of 1984, the best year ever for movies. And while lots of potential hits are being released during the next month or so, some exhibitors are worried that the glut of major studio releases in July will overload theaters and hurt some movies' longevity. If that doesn't happen and box office figures stay strong all summer, the Reporter figures that 1987 still won't break any records unless the rest of the year is also extraordinarily strong.