>>95888336
I'm sorry but no. Conservation of energy means that any manual power is absolutely worthless for a ranged weapon since even with massive mechanical advantages armor vastly outpaces it.
Railguns can not be miniaturized with anything approaching modern or near future technology.
There are a LOT of ways to make guns. Black powder is only one explosive, and not even used in modern guns. To make guns inefficient weapons you'd need to make ALL explosives not exist. This means no dynamite, no blasting for mines, no deconstructing with explosives, no avalanche triggering or explosive bonding, etc. etc.

Consider that guns existed as early as 1400 but spears didn't get completely phased out of warfare until around WWII. That means there's a lot of room for other types of weapons in niche situations, and that spears are just that fucking good. Even today various melee weapons see widespread use in areas where guns are difficult to obtain. Consider also that small arms are largely irrelevant for war. Siege weapons like cannons, artillery, and bombs are much more important.

Also, why would you even want this? What's wrong with guns? What issue do you perceive them to cause?