Take “The Redneck Side of Me,” where Flynnville Train snarl a swampy blues with a menace reminiscent of an era when Charlie Daniels still got stoned in the morning and drunk in the afternoon, and when Hank Williams Jr. got whiskey bent and bragged that a country boy can survive.

That aggressive attitude runs through several country bands getting a major-label introduction in the next month. By all indications, Music Row seems to think it’s time to bring some old-school hiss and swagger into its 21st century sound.

Besides Flynnville Train, an Indiana quintet signed by Toby Keith to his Show Dog Records label, new acts include Cole Deggs & the Lonesome, a Columbia Records group of shaggy Texas and Louisiana boys who mix Tom Petty’s pop smarts with Travis Tritt’s soulful howl, and Halfway to Hazard, a hard-rock-leaning duo who paid more attention to Guns N’ Roses than to Garth Brooks when first inspired to get onstage.

This trend didn’t rise out of nowhere. The success of acts such as Gretchen Wilson and Big & Rich blasted through doors already opened by arena-rock stars Brooks & Dunn, Kenny Chesney, Tim McGraw and Keith Urban—all of whom have cranked up the guitars and kick-drum beats in recent years, even more in concert than on record.

Cutting-edge acts such as Jack Ingram, Shooter Jennings, Bobby Pinson and Hank Williams III melded metallic influences into their guitar-forward sound, incorporating ideas drawn from ’80s hair metal and ’90s hard rock. There’s a reason Bon Jovi is comfortable doing duets with modern Music Row, just as Van Halen, Kid Rock and Metallica flaunted a kinship to Hank Jr. in the past.

But while none of Nashville’s new bands pushes boundaries with the nerve and nihilism of, say, the Drive-By Truckers, they do create a ruckus that doesn’t ignore the meth-lab, girls-gone-wild turn taken by American rural culture in the last decade. It’s a long-needed shift away from the good-neighbor politeness of Lonestar and Diamond Rio, who acted as if all working-class males spent their time at backyard family barbecues bragging about how much they loved their wives, their kids and God.

That guy exists in today’s world, of course, and he should be represented in country songs. But there’s a reason those same guys bolt their garages at night and keep loaded pistols in their bedroom closets. Bands like Flynnville Train, Cole Deggs & the Lonesome and Halfway to Hazard are the sonic equivalent of why police in the suburbs and small towns are busy at night.

Flynnville Train are the most old-school of the lot. They work Chuck Berry riffs into their bar-band rave-ups, and they’re more about all-night partying and rowdy behavior than the other newcomers. Their chunky guitars and hip-shaking back beats recall the Georgia Satellites and Kentucky HeadHunters—indeed, the HeadHunters’ Richard Young co-produced part of the album. And lead singer Brian Flynn testifies like a midnight preacher who speaks from experience when he exhorts his followers to “party like it might be your last good time” on the band’s new single, “Last Good Time.”

Flynnville Train show their colors on a faithful cover of Savoy Brown’s slide-driven “Tell Mama,” and they cleverly turn The Beatles’ “Baby’s in Black” into a boozy Cajun waltz. But they establish their own identity with “High on the Mountain,” a Jim Dandy-style fist-pumper that emphasizes the connotations of the word “high.”

Similarly, a tune titled “Red Nekkid” may suggest the worst kind of country novelty, but Flynnville Train use the exhortation to describe kicking off the muddy boots (and everything else) after work on Friday and getting a buzz on with your gal. It helps tremendously that Flynn delivers the good-time lyrics with such shameless joy, and that the cowbell-ringing sing-along is as catchy as “Honky Tonk Women” or “Keep Your Hands to Yourself.”

Cole Deggs & the Lonesome—whose lead singer’s name sounds like “cold eggs” when announced on the radio—adhere more to familiar Music Row territory. That’s not a surprise, since Deggs and keyboardist Jimmy Wallace have been kicking around town as songwriters for years.

Unlike Flynnville Train, the Lonesome fellows rely on studio pros to do the work for them. It’s easier to come off razor-sharp and radio-ready when using veterans like guitarist Kenny Greenberg, keyboardist Chuck Leavell and drummer Matt Chamberlain.

But Deggs and his band of kin—his brother Shade Deggs plays bass and David Wallace, brother of Jimmy, is on guitar—make good use of these first-call players. Deggs’ songwriting smarts show throughout, and he brings a personality and real-life sense of what it’s like to be a 20-something on the go in today’s South.

“Girl Next Door” tells a tale of a wild knockout of a neighbor who takes him on a joyride before leaving him behind, dazed and more worldly wise. Similarly, “Huggin’ This Blacktop” and “Out of Alabama” combine melodic pop craft and lean rock muscle to update classic roots-rock with modern force. The group’s sweet harmonies add depth to the hold-onto-your-hat realities of the lyrics. This isn’t the sound of married men singing about home and family; this is the sound of young adults just now starting to absorb life lessons as they move from frat-boy indulgence toward something more solid.

Of all these groups, Halfway to Hazard draw the most on modern radio rock, and both David Tolliver and Chad Warrix, who take turns on lead vocals, could pull off convincing karaoke takes on songs by Hinder and Nickelback. Both come from Nashville hard rock bands—Warrix’s band Sodium briefly were signed to Universal, and Tolliver’s Dtox also flirted with major-label A&R scouts before disbanding.

With production by Tim McGraw and Bryan Gallimore, Halfway to Hazard push a hard-rock shine without conceding anything to country radio conventions. But while a couple of songs sweep a listener along with bravado and vocal talent—as on the good-time “Countrified” and the cheeky corporate putdown of “Welcome to Nashville”—too many of the performances go over-the-top while straining to impress.

Maybe it’s because they come from an emo-driven rock world, where every experience has to be delivered with overwrought melodrama, but there’s not a lot of fun or blowing off of steam coming from this Kentucky-born duo. They always choose bombast over subtlety.

The lyrics overreach as well. It’s not enough that the woman in the first single, “Daisy,” straightens the guy out—or, as Tolliver screams it, she exorcises his demons when “she loved the hell out of me.” But she also has to die in the end. Other songs are similarly steeped in high drama, just as the titles suggest: “Die by My Own Hand,” “Devil in the Cross,” “I’m Tired,” “Country ‘Til the Day We Die.”

Fun or not, they’re targeting a young audience who create iPod playlists that pair Chris Daughtry and Rascal Flatts. Flynnville Train, on the other hand, want to pick up what remains of the revolt Hank Williams Jr. sparked three decades ago, and Cole Deggs & the Lonesome want to mine that spot where John Mellencamp and Kenny Chesney shake hands.