they look pretty cool, are these grenades ur making meant to be smooth, im so used to them having those we square dimples all over them, but what u have is pretty cool, get some colour on it and it will make the world of difference, when ur modelling somthing not to complicated like a grenade, it really comes down to texturing to make it look stunning, like sratches on the green paint, dirt in the groves ect... here are a few grenade pics :p
Try adding some procedural textures, and making it very bumpy, and also try some alpha procedural maps aswell, to fade in a lighter brown throu the green paint.
:beer:
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