Different brass from same manufacturer?

[corbanzo]

I sort all my brass out by manufacturer, but was wondering about different brass from the same manufacturer?

Such as winchester.  I have brass stamped, winchester, ww-super, super-x, WRA, etc.  I usually just throw them all together and it hasn't seemed to make a difference, since they all come from winchester, but do you think it would make enough difference in accuracy to matter?  And since they come from the same company, is there really that much variation in the brass to begin with?  The WRA for sure is different... probably cause its 70 years old or so....  but with the others? 

[ricciardelli]

I buy all my brass for each caliber with the same lot number.  Even components from the same company and with the same part number can vary as much as +/- 5% between lots.

[jhalcott]

 I have Sako brass that is from a single factory box. .223 caliber and quite UN accurate. The cases vary in weight as much as 8 grains. In that small case that is a HUGE amount. No wonder there seemed to be pressure problems in an AR15. Most brass is MUCH closer in weight BUT it all varies some. I generally buy 500 cases for a gun, then sort it for visual defects,prep and fireform it. THEN weight sort the empties, keeping the closest for varmint/target use.The rest are sold or used for plinking rounds.