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Idz
03-11-2015, 11:56 AM
Been thinking about how to know if my annealing technique is consistent and produces same state as a commercial 'correctly annealed' case. Since annealing affects the brass strength I thought about placing a known load on the neck to make it egg shaped and measuring the deflection. And by starting low and slowly increasing the load I should be able to find the yield point. By comparing homemade cases to commercial cases I should be able to tell if they are annealed to the same state. Has anybody ever tried this?

Bzcraig
03-11-2015, 07:39 PM
There were a couple of threads recently about annealing, a search should get you there post haste.

justingrosche
03-13-2015, 02:24 AM
It's odd that annealing should be regarded as a Black Art as casting was some years ago. I didn't make any deal with the Devil to cast good bullets. Patients and practice, trial and error were the the keys to my success. I imagine the same goes with annealing. I'm still somewhat new at that game, but I'll persevere! Next for me is the mysterious dark art of neck turning.:evil:

EDG
03-13-2015, 09:12 PM
There is no dark art of neck turning. Success of the material removal process is easy to measure.
Want more precision than the run of the mill .0001 mike buy a .0001 Etalon with the fat barrel and thimble.
Want even more precision buy a bench mike or use a gadget of some sort with a 50 millionths indicator.
To support this precision you need your brass carefully expanded to match the mandrel of the turning too.

gpidaho
03-13-2015, 09:17 PM
Got the neck turning down, still working on consistent annealing. GP

EDG
03-13-2015, 09:46 PM
There was a pretty good thought provoking article in a Handloader Magazine 15 to 20 years ago.
The author was trying to develop an at home technique to assess the effectiveness of neck annealing.

He used a gauge pin and squeezed a case until it contacted the case neck and then measured the spring back.
He was trying a one size pin to test his 6X47 Rem cases.
His method might work if you use a set of .001 increment pins and measure the delta between the neck and the pin when the case first takes a permanent set. To measure the delta, squeeze a .001 smaller pin each time until the brass is permanently deformed. That is the elastic limit.
Another way to measure the effect would be to measure the force it takes to make the case deform.



Been thinking about how to know if my annealing technique is consistent and produces same state as a commercial 'correctly annealed' case. Since annealing affects the brass strength I thought about placing a known load on the neck to make it egg shaped and measuring the deflection. And by starting low and slowly increasing the load I should be able to find the yield point. By comparing homemade cases to commercial cases I should be able to tell if they are annealed to the same state. Has anybody ever tried this?