How much difference in accuracy will 1gr of bullet weight make?

[Oreo]

Just got my scale in the mail today & was toying around weighing some of my 165gr bullets. I found that of about 20 bullets the weights filled the range from 164 - 166gr. So, just out of curiosity, If I'm a perfect shooter using a perfect gun with perfect brass & a perfect powder charge... how much difference will 1grain of bullet weight make in terms of accuracy? Bullet speed? Chamber pressure?

[WILL TERRY]

.......

[layusn1]

Less than 2gr....

[Rangerat]

Go here and play with the parameters. You can see what changing from 165 to 166 will do to the drop at the distance you normally shoot.

http://ammoguide.com/cgi-bin/bcalculator.cgi?sn=VMAtYtWYkj

[lcarreau]

African or European?