The Firing Line Forums - View Single Post - Fire-Forming Brass/ Reduced Loads

brickeyee · February 18, 2006, 12:09 PM

"In other words the brass starts to turn into a liquid. "

Not really.
'Flow' in this case means the material deforms permanently. You have exceeeded the elastic limit.
There are many rounds that are up to the 65,000 PSI mark and case life is acceptable if the rounds are reloaded correctly.
A case head is hardened more than the body of the case to allow sealing in the chamber while resisting the peak pressure.
One of the pressure signs is brass 'flowing' into the ejector hole. This small part of the case head is not suprted by the bolt and under pressure the brass can deform into the hole.
It is still not a liquid.

February 18, 2006, 12:09 PM	#5
brickeyee Senior Member Join Date: December 29, 2004 Posts: 3,351	"In other words the brass starts to turn into a liquid. " Not really. 'Flow' in this case means the material deforms permanently. You have exceeeded the elastic limit. There are many rounds that are up to the 65,000 PSI mark and case life is acceptable if the rounds are reloaded correctly. A case head is hardened more than the body of the case to allow sealing in the chamber while resisting the peak pressure. One of the pressure signs is brass 'flowing' into the ejector hole. This small part of the case head is not suprted by the bolt and under pressure the brass can deform into the hole. It is still not a liquid.