It’s not a great time to be an aging action star.

The relative success of “The Expendables” and its sequel proved there was a legitimate appetite for old-timer butt kickers at the box office. Separate the superteam, however, and the results have been disastrous.

In January, Arnold Schwarzenegger starred in his first leading role in years with “The Last Stand.” Backed by respected action director Jee-woon Kim, the movie fizzled with a $6.2 million opening weekend.

“Expendables” leader Sylvester Stallone opened “Bullet to the Head” last month to the tune of a $4.5 million opening weekend. Although to be fair, that’s an atrocious title for a movie, especially when the commercials suggested “Ax Fight” to be a more appropriate title.

Bruce Willis, the most durable of old-man action stars, tried to right the ship on Valentine’s Day with “A Good Day to Die Hard,” the fifth installment of his most famous franchise. It opened well enough, $36 million over its first five days, but the horrible reviews have caught up with it. “Die Hard” dropped 60% in its second weekend and is on track to be the lowest grossing film in the franchise by a wide margin.

Even the action genre’s younger players have been struggling. Jason Statham’s “Parker” opened in January to a weak $7 million, and Dwayne “The Rock” Johnson only mustered $13 million last weekend for “Snitch.”

So what’s the problem? Traditional, modestly budgeted action movies have definitely suffered from the sustained success of big budget superhero movies. Last year, 31 movies grossed more than $100 million at the domestic box office. Of those, only five were action movies without a fantasy or comic book slant, and three of those were established franchises (“Skyfall,” “Taken 2” and “The Bourne Legacy”).

That leaves “Django Unchained” and “Safe House” as the only original action movies that grossed more than $100 million in 2012. “Django” carried the pedigree of being the latest Quentin Tarantino film, and “Safe House” featured the most bankable star in Hollywood in Denzel Washington.

Even “The Expendables 2,” which featured almost every 80s action star in existence, only managed $85 million at the domestic box office.

Schwarzenegger, Stallone and Willis can take comfort in their enduring credibility at the foreign box office. “Expendables 2” made more than $200 million from foreign markets, and “A Good Day to Die Hard” is going to garner yet another sequel just on the strength of foreign receipts.

Of course, there is a simple solution: Make the movies better.

A “Die Hard” movie that opens in February smells like a stinker from miles away. Want people to take a new Schwarzenegger movie seriously? Don’t hire Johnny Knoxville as his sidekick. And just a few short weeks after a horrific natural tragedy, don’t release any movie called “Bullet to the Head.”

Other than “Die Hard,” at least these movies are modestly budgeted. Pretty much every Statham movie on the scale of “Parker” that opens to around $10 million will turn a profit because the studios know the limits of his fan base.

Still, it wouldn’t kill these guys to try a little harder. Action fans are relatively easy to please. Give us some decent fight scenes, a few clever one-liners and please, stop shaking the camera around like there’s a hornet’s nest in your pants.

Oh, and cast Jean-Claude Van Damme in everything. That guy is box office gold.