Originally Posted By: Chuck H
....That says that 8620 is core hardening from the low teens in the RC scale up to the high 20's. If true, that would make for a great combination of core and surface hardness for a gun.


Thanks Chuck. Those hardness numbers (rockwell c ?) are in a similar range of what 1018 might be. I believe 8620 will or can get a bit harder, but it may be down to the alloy. You're right, I bet the old time makers would give it a close look.