This is a 4987 tri (LOD 0) replica of the Halo Rail Gun modelled in Maya. Both hand painted and smart textures used via Substance Painter along with AO, normal, metallic, roughness and emissive maps. High poly modelled in Zbrush.
Reference: Rail Gun concept art by “Sparth” of 343. | HaloFanForLife. (2022, September 27). Retrieved from http://halofanforlife.com/?p=7525