Bullet weight SD and when is it an issue?

[Sealesniper]

Bought new in unopened box. I don't buy seconds or open box.

 

[Plinker147]

For reference, I just weighed about 40 bullets from the current box of LRAB 129 gr that I have been shooting. I got most between 129 and 129.2 gr. Low was 128.8 and high was 129.3.

Shot about 1/2 this box they have held 1/2 moa accuracy at 600 yds.