It's clear to anyone who cares, that Shogan is using Stannum's concepts for practice purposes. I don't think Stannum is going to kick up a fuss about what is effectively fan art and even then you have more to fear from hurt feelings than criminal damages.
By the way, it looks like you've confused the proportions of the concept such that the gun is significantly shorter and possibly wider in your model. The result is that the pipe on the side of your model looks much smaller than it should.