To start, I'm talking about the Viper Mk IV. Yes, the heavy one. Here's the build.
It's essentially a smaller railgun version of my Challenger build from before. It deals less damage (actually twice the burst damage, but you can't fire the rails non stop even if you can hit with them constantly) and it has less shielding, but has the advantage of being a smaller and slightly more agile ship, making it harder to hit and easier to aim the fixed weapons with.
However, it has a jump range of 33.51ly (see my Challenger build for why that's enough for an exploration ship) and the Plasma Slug railguns, aside from running much cooler than rails normally would (heat is an issue with most Viper builds) also combine with the ship's 16t fuel tank to give it effectively infinite ammo. The missiles are less "renewable" but the main reason I'm flying the Viper over, say, an Imperial Courier, is because you really need 2 of these to clear out Odyssey's surface bases. Since that's all they're for, the 64 rounds in the Advanced Missile Racks are more than sufficient. They also give the ship some punch against the goids in case of emergency. (This is most certainly NOT an AX build, though.)
So there ya go. My Viper Combat Explorer build.