The railgun guy might have been having a giggle with you, but you gave him some actual numbers so I'll give you some actual math to go with them. Your biggest

The railgun guy might have been having a giggle with you, but you gave him some actual numbers so I'll give you some actual math to go with them. Your biggest problem here isn't the launcher, it's the projectile. It's going to be damn near impossible to get a 1 gram projectile more than a couple hundred yards unless it's a dense metal. Doesn't matter how fast it's going, drag always wins here. 10 grams is more plausible, but then you're looking at ~1000ft-lbs cranking energy to get 10g supersonic (@ 40% efficiency) It's doable and you'll only be burning an extra ~100 calories per day for 200 shots. You might get bored though. An airgun will have far worse efficiency most of the time, though it can launch dart-shape things which can go much further for the material density. You mentioned a bow, which is probably the tradeoff point of everything discussed so far. Flight bows are designed for distance shooting, are lightweight and can go 500 yards easily. The downside is you'll need to make the arrows yourself, cause there ain't no supply chain to sell hundreds at a time cheaply. For the "jUsT uSe a hElIcOpTer lol" comment; No, that's not practical, but you CAN get an RC plane that will carry a couple pounds for a tiny fraction of the cost. In terms of how much area it can cover vs supplies needed, that plane is going to be the least thirsty thing on the mountain, assuming you even need to climb it then.