The exact categorization of weapons in F:NV isn't rooted in the logic of transferable skills from real life, but it's arguable they never were previously, either (missile launcher/flamer/minigun, for example). The categorizations have more to do with being clear and consistent with definitions. It follows this basic pattern:

• Does it explode? It's an Explosive.
• Does it use Small Energy Cells, Microfusion Cells, or other energy ammo? It's an Energy Weapon.
• Does it use conventional bullets of some flavor as ammo? It's a Gun.

So while it's accurate to say that Big Guns no longer exists as a category, it's not accurate to say that Big Guns and Small Guns were combined. The weapons in Big Guns were divided among the other weapon skills.

I know not everyone will be happy with this re-organization, but those are the reasons for the change. I hope the reasons are clear, even if you disagree with the decision. Thanks.
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