If you really want to see how accurate your Mp 15 is 2 things should be done. First get some decent ammo like FGMM or Black Hills. 2nd ditch the 4X scope and get a decent scope. I'd recommend at least a 3-9X40. Leupold, Nikon or Weaver all make decent fairly inexpensive scopes. You should be able to get 1.5-2 moa 5 shot groups if you do you part. I have a 4-16X 0n my 516. Last thing you might consider is installing a Geissele trigger. It made a big difference in my 100 yard groups. Groups range ~ 1 moa sometimes better.