Posting this here because it's about load development, not semi-auto pistols or revolvers. Could be long gun or shotgun, but that's not the point either.
Much of the load data one sees in certain calibers, such as .357 Magnum, is listed with an 8- or 10-inch barrel. If it's 8 3/8, I'll assume it's an S&W revolver. Otherwise, who knows? Occasionally, the data uses a no-longer-available bullet or something. Trying to use that data to work up a load with a 4- or 6-inch revolver and a different bullet is at best a directional guideline. Although it's logical to treat the upper end as a hard limit, when you're of necessity or by preference changing components, there really isn't a way to know where you are. It's also hard to compare loads from different sources if they used significantly different barrel lengths, but some of them have notably different max loads listed. A chronometer is of no help, as you can't expect velocities to even be close. Especially with pistol cartridges, you may actually be way over pressure before pressure signs appear.
In the interest of changing as few variables as possible, I realized that a Thompson/Center Contender might provide a good answer. As simple as it gets. Caliber changes are cheap, just pick up a good used barrel on fleabay or GunBroker. You can easily and relatively inexpensively match the odd long barrels that lots of data is published with. (It may even be what the manufacturers used for their load development work.)
You could even easily set up a pressure measuring system on the barrel, which would be essentially impossible on a semi with its reciprocating slide or a revolver. Here's the Pressure Trace system:
https://www.shootingsoftware.com/pressure.htm
I assume 90 percent of people who read this will want to say I'm overthinking it. I'm an engineer. Thinking things through to the last detail is what I do. That's how we get better at stuff. And working without data is little more than wishful thinking.
Is anyone else here doing something along these lines?