worldGlobals.CreateRPC("server","reliable","SendChangedFireSpeedToAll",function(weapon,fSpeed)
	if IsDeleted(weapon) then return end
	weapon:SetFireRateMultiplier(fSpeed)
end

worldGlobals.CreateRPC("client","reliable","PleaseChangeMyFiringSpeed",function(weapon,fSpeed)
	if IsDeleted(weapon) then return end
	weapon:SetFireRateMultiplier(fSpeed)
	if not worldInfo:IsSinglePlayer() and worldGlobals.netIsHost then
		worldGlobals.SendChangedFireSpeedToAll(weapon,fSpeed)
	end
end

--And then you call "worldGlobals.PleaseChangeMyFiringSpeed" on client on button press when needed