Finding a fingerprint on the casing of a fired bullet was once a nearly impossible task. But scientists have at last achieved a breakthrough.

Researchers at Maynooth University in Ireland have now shown they can recover human fingerprints from super-heated bullet cases.

Even better, the prints appear at the "highest level of detail", including pores and ridges.

The details could be sufficient to identify a shooter, although in experiments, the bullets weren't actually shot from a gun; they were heated in a furnace.

"The Holy Grail in forensic investigation has always been retrieving prints from fired ammunition casings," claims chemist Eithne Dempsey.

"Traditionally, the intense heat of firing destroys any biological residue. However, our technique has been able to reveal fingerprint ridges that would otherwise remain imperceptible."