On Feb 24, 1:29*am, Stanley Schaefer wrote:

*And 4140 is hardly
"tool steel". *High chromium and nickel content cuts gas erosion
considerably, back in the early days of smokeless powder, they found
that plain carbon steel barrels that were fine for black powder and
lead bullets just had their rifling go away in a few hundred shots.

Stsn


4140 is what i would call a low alloy steel. Chrome and Moly, but no
Nickel.


SAE grade % Cr % Mo % C * % Mn % P
(max) % S (max) % Si

4140 0.80–1.10 0.15–0.25 0.38–0.43 0.75–1.00 0.035
0.040 0.15–0.35




Dan