Any of you tried a red dot scope on an SKS?

I bought one Chinese SKS with beat-up stock but very good rest of the condition. It shoots 2-3 MOA. So first thing I did was replace the stock with Tapco telescopic stock. This one comes with mounting rail just behind the barrel. I put the cheapest BSA red dot scope available. SKS still shoots the same. Red dot holds fine but only complain is Battery finishes quickly and once you replace the battery. You need to zero it up all over again. But as per my observation goes shooting doesn't reposition the dot