Interesting, Austin. So if Dupont bulk smokeless burned cleanly at about 9000 psi, is it reasonable to assume that cartridge constructions using it generated at least 9000 psi?

Just my limited observations, and I don't have any historic ammunition industry materials, but I've seen and shot a few of the smokeless loads from 1920's shotshells, and some of them are quite stout. Then as now, manufacturers seem to want to produce the bigger, faster loads that are not good for the gun and in my opinon, not necessary. The desire to see how heavy and fast a load could be shot from a gun or rifle undoubtedly caused more than a few ruptured barrels.

Now Calvin, I wasn't born yesterday. I went to high school with a bunch of "dumb farm boys" who are multi millionaires today and spend their winters in Florida, Arizona or Hawaii. Others who are on this forum spend time buying new $300,000 combines or $250,000 tractors and manipulate their grain sales through savvy trading. We hunt on land west of Dodge whose owner spends his winters in Naples, Florida and sometime we plan on hunting Arizona with a farm boy who lives in Scottsdale Arizona part of the year.

My uncle used to pull the "dumb farm boy " expression on me when he was chairman of the chemistry department at the University of Arkansas and farming 160 acres outside town. As for me, I'm just an old retired heavy equipment operator and now talk to some people and write a few letters.

Bruce: Did any of that "heavy equipment" happen to have 4 engines and a 54ft cargo deck??

It would, Richard.

Here's several of us ol country boys hangin around the pick up truck.
L to R:
James Van Blaricum, Pratt Kansas, a retired driller.
Bill Bolyard, Mich, a retired timber cutter
Me, a retired equipment operator
Charlie Herzog, Ste Genevieve , MO a retired construction worker and small farmer
Don Hornung, a Dodge City farmer

I think Bruce's "heavy equipment" had 8 P&W J57's

That also. With blasting charges for surface mining operations.