In my experience/opinion its a little of both. Again, the 20 is an absolute laser out to around 400 but every round has an operating envelope and when you get outside of that you're going to have problems. There is only so fast that you can reasonably send the 20 cal pill downrange and it will bleed velocity pretty quick. From what I've seen 400 yards +/- is about the range that you can expect sub moa accuracy out of this round under field conditions. On paper targets off of a steady bench at known distances is different. But for killing, will it hit farther out? Of course. But consistently, effectively? Not to a level that I'm ok with. Re pressure- my gun shoots 23.1gr of H4198 very well. That doesn't mean that yours will and it should be noted that this is about .5gr above max in a comparable 223 load. Whenever you start pushing the upper regions of case capacity, charge weight, pressure curves etc you're going get to a point where you have little wobbles in your results. If I push any harder than the above load I can get phenomenal accuracy with no pressure signs, sometimes. Other times its a stick bolt, a spike on the chrono or an unexplained flyer. When you push velocity thats what you get. Again, and I really can't overstate this- I am by no means an expert on any of this. These are just the things I've seen with my gun.