The first gas blowback M249 made by VFC got a version that meets Japanese regulations. Hyperdouraku got their hands on one and Mister Moro does a review of this GBB LMG... "The M249, the best-selling squad support weapon (SAW) developed by Belgian FN, has been updated with a VFC gas blowback gun. A video review of VFC gas gun M249 GBBR (JP version)."
Read further on here and below is the video review: