Over annealing?

[billbmcleod]

So what happens when you over anneal a brass case. I have read it is dangerous but what are the dangers.
I suspect that the case might separate and cause an obstruction or over pressure but I have not seen specifics. I do destroy any cases that have gotten too hot except for a few I use to set up my contraption before each run. I have drilled holes in these so they will never see any powder.
This may have been covered in the past but I could not readily find it. A refresher is always great.

 

[legi0n]

if you impart annealing temperatures (650ºF or more) for long enough (10secs +) to the case head, the head will soften, and, upon firing it will expand to the extent of having loose primer pockets

if you oversoften the case neck, the bullet tension will be quite low allowing for "recoil bullet setback", uneven accuracy and even bullet fall (haven't heard of any confirmed cases)

the case neck will harden again when sizing but the head won't


let's not forget, at 450ºF brass anneals in like 1 hour so that's not an issue