Gentlemen, first let me say that I really enjoy reading this forum. I have picked up several tips, ideas and a wealth of info. here. There has been an issue that has just itched my gray matter for a while. I have read several times (not necessarly on this site) statements like... "My gun won't group that well at 100 yds. but will shoot a 2" group at 300". Or conversly, it will shoot bugholes at 100 but won't group at 300, 400, etc. Could you guys enlighten me on how this can happen, the physics, the external factors, or other contributors? I just can't see how this could be. Thanks for your input in advance.