Brass weights

[misskimo]

Hey. Well I'm into loading for perfection. And yeh. Maybe I don't need to be so , I have rem brass and after a few test shots trying to find my sweet load. I desided to weigh my brass.
30-06 rem brass weights range from 193 g to 198 g. I have about 60 out of a bag I bought new , Do you think I should seragate the difference. ? It seams to me why I would get a odd ball shot when grouping with one load if let's say I loaded up 3 that the brass weighed 194 g and one that weighed 198 g.

 

[Unclenick]

Need to learn to use the search feature. There have been three threads on this in the last couple of weeks. This is probably most relevant:

http://thefiringline.com/forums/showthread.php?t=434537

Bottom line, though, 70:30 cartridge brass is 8.53 times more dense than water. 3 grains of brass weight difference in .30-06 is about 0.35 grains of water capacity. Powder charge for constant pressure is approximately the square root of the difference in water capacity. If we assume a 48 grain powder charge, then this will be around 68 grains water capacity vs. 68.35 grains water capacity. So the powder charge equivalent difference will be approximately 48-48×√(68/68.35) or about 0.123 grains equivalent difference in powder charge. So little your scale will have trouble measuring it.

The only possible advantage, then, is in identifying which tooling the brass came off of by its weight. You may or may not want to do that. I illustrate this in my second post in this thread:

http://thefiringline.com/forums/showthread.php?t=434756&highlight=brass+weight

 

[misskimo]

Thanks alot for the good info. Well I loaded up 4 loads. One with the lightest weight brass , 2 of the same weight that was in the middle of the weight group and 1 of the heavy ones with my match load I did last night. 49.5 g of imr 4064 with a nosler 165 g ballistic tip.
The 2 of the shells that weighed the same shot bullet hole at 75 yards. The other 2 with the wide weight margin shot 5/8" group. I will load up 8 more and do a better test

 

[temmi]

I say this a lot (cause I do the same thing you do)…

There is very little to be gained weighing and sorting brass which is not fully prepped…

Trimming all brass to uniform lengths
Uniforming primer pockets
Deburring flash holes
Uniforming Case neck thickness…

One thing is this removes all “extra" brass so you are not judging a case weight by the extra brass found in a long neck and/or thick primer pocket…


All that said, after I prep my brass I weigh and sort it in to .5g lots, for 30 cal or greater… 93.0-93.4 , 93.5-93.9…. This takes a lot of brass.

Then I weigh all bullets into groups of .1g. this will take a lot of bullets too

And I weigh every charge

But this will give you the ability to weigh completed cartridges .

 

[misskimo]

Well. Thanks for the info. After more shots today. I think I will buy nosler brass from now own.
I shot 3 sets of groups of 3 each. I could see the groups difference , one group seam to be 7/8" off from one. The other was around 1/2" I shot 3. 194.3 , 3. 194.9. And 3. 195.5. Case weight was prep with no primer