I don't disagree with you guys in theory, but in practice, my lightweight precision rifles still hold .5 moa for me, just like my heavyweight rifles do. I'm using precision rifles as an example, as the accuracy is a known quantity, unlike the ultralight AR's or other builds. Bartlein, Lilja and Kreeger barrels mostly, though I have had others as well. GAP, APA, AI and others for the builds. Ekeing out maximum accuracy is easier with a heavier gun. A lighter gun needs more technique and practice, but can still do the same job. The forgiveness of a heavier gun is what keeps pros using them when it counts.