If your groups were with open sights and off hand I would say good job. If with a scope and off a rest I would say look for a problem (with the gun or shooter)or change components.

My son's regular Optima shoots around 1.5" with a 250 Shockwave and 80 to 100 gr of Pyro P if I shoot it, around 3" when my 13 year old shoots it.

I don't accept a load till it shoots under 2" at 100 yards off a rest, especially if its with a scope, otherwise I limit the range I will shoot with that gun and load combo. With my Magbolt the best grouping bullet I have tried is the 348HP Powerbelt over 100gr of 777 2F, it usually groups around .75" (sometimes better) if I do my part. Most of the loads I use shoot under 1.5" and they include sabot bullets, conicals and roundball. Some guns, like my Magbolt, like heavier bullets, others may like lighter bullets or any bullet, each gun is unique in what it likes. That is what makes this sport so much fun and gives us all a good excuse to go shooting more.