Best method for counting bulk brass, 9mm 45acp etc

[tjsudbury]

seller is either piss poor at math, or a rip off

 

[Tinman204]

When I'm doing pistol brass I weigh 100 and then use that weight as my baseline.

After I'm at the right weight for say 1 or 2k I throw in an extra hand full or 2 which makes up for any difference.

 

[baldabe]

seller is either piss poor at math, or a rip off

Atleast twice in the thread OP has said that the seller made it right.

 

[tjsudbury]

Atleast twice in the thread OP has said that the seller made it right.

so, not so good at math, or major brain fart would be a more appropriate comment

 

[Cranberry]

So, having too much time on my hands, I did some statistical analysis.

Random sample of 20 uncleaned, un-decapped 9mm range brass with mixed headstamp:

Average weight: 63.35 grains
Standard Deviation: 2.12

Calculating average weight (in grams) from varying sample size:

5 cases = 21g = 4.2 per case
10 cases = 42g = 4.2 per case
50 cases = 205g = 4.1 per case
100 cases = 410g = 4.1 per case

Applying the 4.1g average to my bucket of 9mm awaiting processing:

Weight = 1227g
1227 / 4.1 = 299
Actual number (from manual count) = 301

So, 0.66% out. Using the average weight method based on a reasonable (50-100) sample size seems to be accurate enough for most purposes.

btw: weights in grains determined from my Hornady electronic scale. Weights in grams determined from a $20 Starfrit electronic kitchen scale.

 

[zuke]

When I sell mine they're as picked. That include's free sand and grass.That's why I actually count them

 

[dakotamar]

I just line them up in a 10x10 grid and dump them in a bag, quick and easy.

 

[Avalonthas]

I usually weigh 100 pieces and apply that to the entirety of the batch