Accuracy

First let me start by saying that I have been shooting for 40 years, but have never done any reloading and only used factory ammo. I also have never done any precision shooting and have never needed better than hunting accuracy (nothing beyond 250 – 300 yards). I have just become curious as to whether the accuracy of a good rifle was more of a consistency thing, or an actual load thing.

OK, I understand that most, if not every, rifle will have some ammunition that it will shoot better than others. However, how much difference is there in accuracy between ammunition that the rifle “likes” and ammunition that it "doesn’t like”?

I understand that differences in ammunition (bullet weight, type of bullet, amount of powder, type of powder, etc.) will change the POI, but if the ammo is consistent how much will it change the accuracy/grouping of the shots? If you have a rifle that is capable of MOA accuracy with the right ammo, will the difference in ammo make it a 2 MOA, 3 MOA, 4 MOA rifle? Assuming that the ammunition is quality ammunition, and is consistent from one round to the next, will it change both the POI and the accuracy, or just the POI?

Thanks.