Metallica are about a quarter of the way done with their new album. The news comes via guitarist Kirk Hammett, who assured fans that the band are hard at work on the follow-up to 2008's Death Magnetic.

"We have a lot of good songs," Hammett told Billboard. "The songs are ever-changing at this point. Nothing is etched in stone. We still have a lot of material have to sift through, still. We have well over a dozen songs and we still have well over two or 300 riffs, too, so it's hard to say at what point we actually are in in the project. I don't think we hit the middle point yet. I would say we're at the 25 percent point, maybe 30 percent point. It's hard to say, but I mean we are working on it and there are songs and we're making plans to write more songs and record."

The 2-300 riffs has apparently been whittled down from the 800 that James Hetfield said they had in the summer of 2012. And last month Lars Ulrich said they have 20 songs written so far. For Hammett, the amount of time they spend on albums is par for the course and something that has been written into the band's lore.

"Whenever we go into the studio, it becomes such a huge sort of thing in our lives that it does take on monstrous proportions," he continued. "It takes up a lot of space in our lives. Yes, you can look at it as something monstrous, for sure — and we've made movies about it, so there you go, man."

However monstrous the new album may wind up becoming, we can't expect them to spend much time on it this summer. Hammett's Fear FestEvil convention is currently taking place in San Jose, Calif., and Metallica are also prepping for a tour. THey have 13 festival dates booked between May and mid-September, with 11 shows in Europe and the other two taking place in the U.S., at Rock in Rio USA in Las Vegas and Lollapalooza in Chicago.

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