I'm really into rocketry and the space program, so I thought this might be a good way to pay tribute to the thing that pretty much all of 70s & 80s sci fi is inspired and enable by -- the rocket engine. My first idea is to put mach diamonds like this:
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down the barrel. Here's what I've got so far:
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For the rest of the gun, I don't have any specifics yet, but I'm thinking of having a texture similar to the outside of the RS-25, or SSME (Space Shuttle Main Engine):
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