base.css.sass

.sortable-item
  cursor: move // IE fallback
  cursor: -webkit-grab // Chrome and Safari fallback
  cursor: grab

  &.ui-sortable-helper
    cursor: move // IE fallback
    cursor: -webkit-grabbing // Chrome and Safari fallback
    cursor: grabbing

base.js

jQuery(function($) {
  $(".sortable-item").parent().sortable({
    axis: "y",

    update: function(event, ui) {
      var resource = ui.item.closest('[id^="index_table_"]').attr("id").replace("index_table_", ""),
          id = ui.item.attr("id").replace(/\D/g, "");

      $(document).trigger(resource + "_sort", { id: id, position: ui.item.index() });
    }
  });

  $(document).on("tips_sort", function(event, params) {
    var url = "/admin/tips/" + params.id + "/change_position";
    $.ajax(url, {
      type: "PATCH",
      data: { position: params.position }
    });
  });
});

tip.rb

ActiveAdmin.register Tip do
  config.sort_order = "position_asc"
  config.paginate = false

  index row_class: ->element { "sortable-item" } do
    column :title, sortable: false
    actions
  end

  member_action :change_position, method: :patch do
    tip = Tip.find(params[:id])
    tip.insert_at(params[:position].to_i)
    head :no_content
  end
end