Suprise Weighing 6.5-.284 Norma Brass

[Terry]

Just for fun I checked the case capacity of the heaviest and lightest pieces of 6.5-.284 Norma brass.
Filled both cases with D79 ball powder. The heaviest case held 1 full grain more powder that the lightest case.
200 pieces of brass. Lightest 195.12 gr. Heaviest 197.13 gr.

Terry

 

[Nomad47]

Hmmm, I would expect it to be the other way around. After all, if both cases are identical on outside dimensions, then the lightest case should have less brass on the inside, therefore more capacity.

But I believe dmoran and others have said that there is no relationship between case weight and case capacity.

 

[Shynloco]

Hmmm, I would expect it to be the other way around. After all, if both cases are identical on outside dimensions, then the lightest case should have less brass on the inside, therefore more capacity.

That makes two of us.

[/quote]
But I believe dmoran and others have said that there is no relationship between case weight and case capacity.
[/quote]

No sure on that one if dimensions are identical.

 

[jonbearman]

Deliberatly load it and shoot it in a group that matches the closest in weight and I will bet it wont matter.I would like to see a spread sheet that proves that a grain of capacity would make it not shoot accuarate enough to be in the group at the end of the day.

 

[M-61]

Really odd.....makes me wonder if since BRASS is principally an alloy of copper and zinc (which do not weigh the same).(Plus other metals) If the proportions of the two are different in one run of "BRASS" to another run of "BRASS" you still wind up with "BRASS" but they would not weigh the same. I wouldn't think they would vary in composition to that extent but there is no reason to assume that each 'ingot' ( or run )or whatever a block of brass is called) supplied by the brass manufacturer would be identical.
If my idea is the right assumption I am positive there are members here on this site that could produce the correct terms. Short of this the only thing I would think of was 'voids' in the end product which I don't think is even close to correct and after 50,000psi slams the case at the very best those voids are gone. I am sure someone will give an answer that makes sense. Interesting.

 

[broncman]

Want another surprise? Get your tin snips out and a peice of old brass. Now trim a piece off the neck and weigh it. Keep trimming till you get a 2gr piece and see how small it is!

Differences in extractor groove cut could be almost that close!

 

[Shynloco]

Want another surprise? Get your tin snips out and a peice of old brass. Now trim a piece off the neck and weigh it. Keep trimming till you get a 2gr piece and see how small it is!

Differences in extractor groove cut could be almost that close!

Wouldn't surprise me at all. But if fired from the same rifle and using what Jonbearman writes, the brass would go through the same extractor and you'd still be close in brass weight which is optimum in my book for accuracy when it comes to the brass component likeness.