I have an in-line muzzleloader that I plan on hunting with in the next few days. I'm shooting 250gr Hornady hp sabot rounds propelled by 150 gr Pyrodex pellets. The gun is zeroed at 100yds and shoots 2" groups consistently from a rest. Now the mystery I'm dealing with is that at only 50yds it shoots LOW about 4" consistently from a rest. ?????. Anyone ever heard of this? To me this goes against the physics of bullet flight. I shot half a dozen rounds from each distance at rest today cleaning after every shot and I just can't wrap my brain around what going on.