Traditional charcoal & bone case color

[Craig Budgeon]

Edgar, earlier you commented along with myself and Michael Maffia that .002' depth seemed shallow to you and you expected depth to be .005' or more. In the past I have repaired 2 cracked receivers where I had to mill through the case which I found to be no more than .003 deep. I expect your experiences were different than mine.

[edgarspencer]

Originally Posted by Craig Budgeon

Carbon steels have a carbon content of 0.4% or higher

Originally Posted by Michael Moffa

Carbon Steels usuaaly start with low carbon like 1008 and go up to 1030,

Craig, you and Michael seem to differ on the Carbon content of plain carbon steel. I am most familiar with ASTM A216, as that was our daily bread and butter. That document indicates an allowable max C of .030%. A 216 (and SA216 for ASME) are cast steel specifications.

Originally Posted by Craig Budgeon

Edgar casehardening depths vary from less than.0005" (speed case) to .030" (carburize)

Originally Posted by Craig Budgeon

Edgar, earlier you commented along with myself and Michael Maffia that .002' depth seemed shallow to you and you expected depth to be .005' or more. In the past I have repaired 2 cracked receivers where I had to mill through the case which I found to be no more than .003 deep. I expect your experiences were different than mine.

You give fairly broad ranges of case depths here, and indicated you found depths of .003". That would certainly seem to fall into, and at the lower ranges.

As I indicated earlier, Parker began using forgings containing higher nickels, and our spectrometer indicated, on a VH20 to be much closer to a .35C NiCrMo alloy. That VH 20 is floating around New England somewhere, and can be identified by the 5/16" dia. etched circle on the watertable. That was a gun I owned and I did the analysis in order to select an electrode, and repair a crack in the top tang.
Yes, my experience was different than yours, but I suspect if we both sampled many more Parker forgings, our experiences would cross, and vary significantly.
A sidebar I found interesting; Parker regularly purchased forgings outside, as well as running their own forge shop. One well know forge was the Collins Company, in Collinsville, CT, and Billings & Spencer, in Hartford. If Parker produced some of their own receivers, I don't know where their ingots came from, as they did not pour steel in their foundry.