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Dave very informative, learned a lot of new things about turned cases.  
Thank You, MIKE-T

Thanks guys, 
I hope this has answered some questions about machined brass.
I am going to take it a little further,   A neighbor shop building a new lever gun has a hardness tester in their shop and has offered to let me check the hardeness in the case heads on brass cases.  I am going to compare a belted mag case to a standard 30-o6 and a 38-55 to see just what the actuall differense is.  Will post the results as soon as I can get it done.
I have not made any brass for modern high velocity chamberings as I know the case head will not hold the high pressure.  and brass cases for modern chamberings is readily available.  So I only produce cases for the old chamberings and lead bullet loadings .typically in the 1400 -1600 fps  range, but have chronographed loads up to 1800-1900 fps with great results. for big game hunting loads.
Although one customer that is manufacturing a 70 caliber bolt action gun for dangerous game use, has been loading a 1000 gr. bullet at around 2200fps,   ouch! makes me hurt thinking about it

Thanks,
Dave Casey

Frank,

I have always used  .200 thickness in the head in all cases unless ordered otherwise for more or less capacity,  and most all drawn cases I have measured also have from .180-.200 thick solid heads.  The old balloon and transitional cases were much thinner. 
 
And you are correct, the the primer pocket in the  head is  the problem with  pressure.swaging open due to the pressure exceeding the brass strength.  The same happens with too hot of charges with drawn brass 
What I have found ,as a rough limit, that 38,000 CUP is the limit for pressure in the C360 half hard bar. no matter the size of the head.

I have used Naval bronze C485 and also Phosphfor bronze C544 to produce a stronger head of the same dimension, to with stand a bit higher pressures , but the cost of material in todays market is absolutely prohibitive to use those alloys.

Interesting your comment about the neck collapsing, I have found the tendency for the neck to collapse is from to low of pressure to expand the neck and seal the chamber when breech seating. on cases such as the 32-40 etc.  I found increasing the load a grain or so solved the tendency to collapse the necks. and stopped the sooting of the case mouth as well.

It will be intersting to see what the actual difference in hardness of the three cases that shows up in the test.

Anyway, I am really not interested in producing cases for high pressure loadings, I am mainly concerned with the old obsolete and other  chamberings that use lead bullet loadings and velocities ,so the C360 is just fine for what we are doing and gives plenty of a strength factor in the head for the pressure devoloped for those purposes.

Thanks,
Dave Casey