If anyone is interested, I was working on some Lake City 5.56 brass today and had just finished sizing, trimming, cleaning, etc. when I wondered how consistent the weights were. I had a batch of 179 ea with 2009 headstamp and 105 ea with 2003 - 2008 headstamps (about 50 of the 105 were 07).
Results:
90% were between 91-92.5 grains (1.6% weight variation)
-94% of the 09 brass was in this weight range
-82% of the 03-08 brass was in this weight range
61% were between 91.6-92.4 grains (0.9% weight variation)
-68% of the 09 brass was in this weight range
-50% of the 03-08 brass was in this weight range
30% was between 92.1 and 92.4 grains (0.4% weight variation)
Results:
90% were between 91-92.5 grains (1.6% weight variation)
-94% of the 09 brass was in this weight range
-82% of the 03-08 brass was in this weight range
61% were between 91.6-92.4 grains (0.9% weight variation)
-68% of the 09 brass was in this weight range
-50% of the 03-08 brass was in this weight range
30% was between 92.1 and 92.4 grains (0.4% weight variation)
