I modelled and rendered this popular machine gun with 3ds max and marmoset. Max files has material setup.
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In the rar files there is 2 files.
1-) Model itself with all inner parts.
2-) Texture files.
2-2) In the texture files there is 5 set textures with uvw mapped. (non overlapping)
1-) Body; 4k texture set metalness workflow. 2-)Inner parts; 4k texture set metalness workflow. 3-)Reload; 4k texture set metalness workflow. 4-)Barrel; 4k texture set metalness workflow. 5-)Tripod; 4k texture set metalness workflow. (partly overlapped)
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You can open file with, 3ds max 2017, 3ds max 2018, 3ds max 2019 or new versions.
And also fbx and obj format supported.