Not so! Modern barrels are typically either 4130 or 4140, it's not really that expensive either. Mild steel isn't used in any barrels.
absolutely. Especially on pumps where the bolt locks into the barrel.
I have parkerized some differential heat treated 4140 and you can see the hardness in the colour difference of the park. I parkerized my rem barrel and it came out pitch black, just like hardened 4140. The 870 receiver I did came out lighter grey which matches 4140 hardened in the mid 30's. This really means nothing, but it confirms to me that the barrels are hardened alloy. Also, 4140 is not expensive steel in this day and age. It's one of the most common alloys used for all kinds of things.
Anyways, a hardened 4140 tube is not easily dented which is why I think the super thick profile barrels are really just needlessly heavy to haul around.




















































