What is exceptable brass weight deviation?

[padreweis]

I am playing around with weighing some 300wm brass. Can anyone tell me what accecptable differences should be? For instance out of 100 cases the weight ranges from 234.5 grains to 240 grains. So basicly that gives me a 3 percent deviation.

80% of them fell between 237 and 239 grains which is less than 1 percent. Should I just use those as my working pool?

Any clarity someone can provide would be awesome.

[Kevin Thomas]

Sinclair recommends a variance of 1.5% as being an acceptable range, and that's one that should leave you with a workable amount of brass. This is the standard that I've held my match brass to for some time now, and I have no complaints with this tolerance.

Weigh them all, separate them by .1 grain increments and see how they fall on a bell curve. Discard those that fall outside the 1.5% range and keep those in the middle as your working brass. Should be good to go from there.

[padreweis]

Originally Posted by Kevin Thomas

Sinclair recommends a variance of 1.5% as being an acceptable range, and that's one that should leave you with a workable amount of brass. This is the standard that I've held my match brass to for some time now, and I have no complaints with this tolerance.

Weigh them all, separate them by .1 grain increments and see how they fall on a bell curve. Discard those that fall outside the 1.5% range and keep those in the middle as your working brass. Should be good to go from there.

Thanks Kevin! That answered it perfectly.

[Kevin Thomas]

Glad to help!

[blackdog]

Kevin - now will you please start making some 300 win mag brass again that meets those standards?!?!?