Re: Would the peasant railgun be possible in GURPS?
 

Well, yeah. It assumes D&D rules ignore physics, until at the specific point the player trying to get away with the peasant railgun suddenly wants D&D to have rules for physics, so the railgun does something.

Sorry, nope. It continues to ignore physics forever, because D&D has no physics. It has game rules.

Re: Would the peasant railgun be possible in GURPS?
 

This is why using ring gates and infinite falling to generate rods from god is superior.

D&D does have rules for some physics. The peasant railgun neglects to engage with them.

Re: Would the peasant railgun be possible in GURPS?
 

However, the physics in Dungeons and Dragons are so limited and obtuse that they barely count as physics. The peasant railgun interacts with the physics, if I remember correctly, in such a limited way that the Dungeon Master gets to decide if it works. Realistically at an Adventurer's League table, it would never fly (the peasant railgun and the thing being thrown). Now, would it work in GURPS? That's also up to the Game Master, like in Dungeons and Dragons, because in a wacky setting, it totally could. RAW? I don't think so.

Re: Would the peasant railgun be possible in GURPS?
 

Even if you allowed your peasants to pass it foward with a single held action that wouldn't give it any momentum because it didn't experience any acceleration. It would just have teleported from the back of the line to the front of the line. +

Re: Would the peasant railgun be possible in GURPS?
 

In GURPS, that would be a kind of pseudo-velocity drive.

Re: Would the peasant railgun be possible in GURPS?
 

Strength is a valid concern about the speed you'd generate passing an object, like it should be a combination of DX and ST like how Control Points happen in Technical Grappling