Weighing Brass Cases

[rquack]

This is a new dimension in reloading for me. When does the weight of a case demonstrate such a divergence from the average that it should be culled from your inventory? I have 60 previously fired Remington 7mm-08 cases; all freshly trimmed, tumbled, flash holes de-burred and re-primed. The weights vary from 165 grains to 172 grains, as follows:
2x165
20x166
11x 167
5x168
15x169
5x170
1x 171
1x172
I realize that the case weight is only being used as an indicator of capacity. All are measuring within .0015" in length. Some short cases are heavy, while long ones are light; increasing weight did not directly correlate to increasing length.

How tight must they be sorted to optimize accuracy? When do differences become insignificant?

 

[dragger201]

In the accuracy side, if the outside dimensions are the same but the weight is different then that means either a higher density in the metal or the thickness varies. In either instance, consistence will be effected. To what extent, I wouldn't claim to know, but I'm sure someone does or has access to the math to figure it out. I did know a few BR shooters who would separate brass by weights.

I used to use brass weight as a way to keep an eye on "thinning". Every time you have to "trim" you end up removing metal(obvious) but that metal is coming from somewhere else. I may have been overly cautious, but I would average a set of brass and then weigh after 4-6 reloads and any that had dropped in weight by 5% I discarded. On very light loads I didn't worry about weight until 10 or more reloads. How often I did brass weights was also guided by what I was seeing when I trimmed.

 

[BK]

Really, dirtbag, you are trying to sell designer handbags here?

 

[usmc 89]

i do sort my brass by weight for the fact if you have a deviation in weight you will have a deviation in velocity. you may not notice this at 100 yards or even 200 but the further you are shooting the more this becomes apparent. spend the money on the better brass lapua norma and nosler to name a few. i know they are expensive intitially but i would rather spend the money and cull fewer and get more reloadings out of the quality brass then buy the cheaper stuff. the only reason i got rid of my 338 ultra was the fact that nobody made good brass for it.