This salvo weapon is just a FAL with two barrels. It was ironically designed by Stefan Janson who previously worked on the Enfield EM2 which lost during NATO trials.
As for the front image of the rifle, It may have been modified with an AR10 sight later on in the SALVO programme.
Patents: http://www.google.com/patents?id=IoJgAAAAEBAJ&pg=PA1&dq=&source=gbs_selected_pages&cad=0_1#PPA1,M1
Source: http://www.rediscov.com/spring/VFPCGI.exe?IDCFile=/spring/DETAILS.IDC,SPECIFIC=594,DATABASE=objects
