The English guys are throwing the line “safe for steel” around a bit too much. We saw bulged Browning A5 barrels perhaps a decade before steel was a thing, and none of those loads that did that were hitting 1300-1400fps. A gun with 100 year old solder between the ribs might last forever running 2 1/2” low pressure lead loads, but, I’m not interested is seeing what even the lower velocity version of English steel shot loads could do to those guns.
We don’t have that distinction between steel loads, here. Regular steel loads sold here don’t impress the birds anymore than they impress me.
Best,
Ted