MCA Records said yesterday it has already posted more than $ 300 million in domestic sales, making 1992 the best year in the company’s history.Although the label had no single break-out success like Liberty’s Garth Brooks or Mercury’s Billy Ray Cyrus, it credited its success to a diverse field of releases that each performed well. Albums by Elton John, Bobby Brown, Mary J. Blige, Wynonna and George Strait led the charge for MCA, which should add to its total with the release next week of new discs from country’s Reba McEntire and hot new R&B act Shai. The company’s performance is even more notable given the absence of a major rock ‘n’ roll talent–along the lines of U2 or Guns N’ Roses–on its roster. Figures for 1991 domestic sales were not available. However, a representative for MCA said the company’s previous best year for domestic sales was 1989′s $ 269 million. The company is on a calendar fiscal year. The rep declined to say whether the 1992 sales would create a profitable year for MCA Records, citing company policy. As with all record companies, the profit margin varies from artist to artist, with marketing and promotion costs affecting the final bottom line. It’s not clear how MCA’s performance ranks with such traditional industry powerhouses as Warner Bros. Records or Columbia Records, since parent companies don’t usually break out earnings for individual labels. Still, MCA’s strong chart success in a recession-plagued year in the record industry should leave it standing tall among its competitors. “What’s great is that a whole bunch of good things have happened with a great many artists across the musical spectrum,” MCA Music Entertainment chairman Al Teller said. “It’s always fabulous to have one of those megaplatinum records, but ultimately it’s better business, and you build a stronger company, by having success spread over a number of acts.” Double-platinum albums, granted to albums with sales in excess of 2 million copies, were generated by the group Jodeci and solo artists McEntire and Wynonna , while the company said Strait’s soundtrack to his film “Pure Country,” Blige’s debut album “What’s the 411?,” Brown’s “Bobby” and John’s “The One” were on track to join them in the double-platinum ring by year’s end. The company also earned platinum albums for Vince Gill’s “I Still Believe in You” and Jimmy Buffett’s boxed set “Boats, Beaches, Bars & Ballads.” Gold records (awarded for sales surpassing 500,000 units) have been achieved by Patty Smyth, Lyle Lovett, WRECKX-N-Effect, Erik B. & Rakim, Strait’s “Holding My Own” and “Ten Strait Hits,” Mark Chesnutt, Marty Stuart and Trisha Yearwood. The turnaround at MCA comes after a period of relative turmoil that ran roughly from late 1990 through early 1991. The company’s direction was almost daily grist for the ever-volatile record industry rumor mill, fuel added to the fire with the announced departure of Elton John and Tom Petty to other labels, although both still owe albums to MCA. Teller has since shuffled executives in his promotion and marketing departments and stuck to a philosophy of building the label by affiliating with such heavyweight industry players as Andre Harrell (who signed a reported $ 50 million deal to create Uptown Enterprises earlier this year), Louil Silas (a senior MCA executive who was given his own label) and powerful managers Allen Kovac, Arnold Stieffel, Randy Phillips and Gary Kurfirst, all of whom are tied to MCA with label deals.