g.willikers
Here's a neat chart comparing 9mm cartridges from around the world.
https://en.wikipedia.org/wiki/9_mm_caliber
I made my own smaller chart out of frustration.... did not know there was one.
Checking the brass base size my measurement vs the chart
9x19mm 0.389" [0.391" chart]
9mmSuper comp 0.385" [0.384" chart]
9x23mm 0.387" [0.392" chart]
9mmMag 0.388" [0.392" chart]
g.willikers If the goal is more power than the 9mm delivers, check out the 9mm Major loads as used in competition.
I can't tell you how many emails I get from guys who want me to ream out their 9x19 Tokarev to 9x23 so they can load the hot handloads.
I try to tell them that 9x19 can make more recoil then you can handle with any slide and recoil spring combination they have.
The 380 can make more recoil with handloads than any slide mass and recoil spring combination you can present.
Maybe some gunsmith has converted the massive slide Desert Eagle to 380, and it can take 380 full power without the slide hammering the frame, but I doubt it.
158 gr bullets and Power Pistol powder in the 380 or 9x19 can just about break my wrist in a work up.