Way back when, I tried many different .380acp loads in my PPK clone. The 102gr. Golden Sabre was one of the most accurate loads. And it was very reliable. Its shape is much closer to ball ammo than something like a Hydra-Shok, or even a Gold Dot. So reliability and accuracy camer first.
Then I tested some in wet newsprint, and it gave about 75% of the penetration and "wound channel" of the 9mm round I was comparing it to. It mushroomed reliably with up to 5 layers of denim in front of the newsprint. The 9mm would mushroom reliably up to 7 layers.
I didn't do expansion testing on any other rounds, because I had already decided on the Golden Sabre for reliability and accuracy. But it seemed good enough to me.