The judge who freed an alleged cop-shooter on a pittance bail last year gave a sweetheart sentence yesterday to a naval reservist who sold an assault rifle to an undercover cop.

Dominick Bunch, who was hauled off a military flight from California to Afghanistan so he could face justice in New York, sold an SKS assault rifle to an undercover cop for $720 across the street from a school on Herzl Street in Brownsville in June 2009 and pleaded guilty in exchange for a three-year sentence.

But Brooklyn Supreme Court Justice Gustin Reichbach sliced Bunch’s jail term to six months.

“It’s an absolute outrage,” said Brooklyn DA Charles Hynes.

The judge did not return a call for comment.

Reichbach created a flap when he freed alleged gunman Elijah Foster-Bey on $100,000 bail after the suspect allegedly shot an officer in East New York last October.