“I wouldn’t have thought they did. “
I went looking for the article that did a comparison test but could not find it. There appears to be a lot of differing opinions. Several articles talk about the failure to penetrate. But that is the intent. The Glaser is very soft and faster than a similar FMJ because it is lighter. It transfers all of its kinetic energy on impact, which I’m guessing would be one hell of a hit. I use it because the .380 Glaser round is known for ricochets and I don’t want to risk hitting an innocent bystander. Note that the .380 has a 3.5 inch barrel and you musty practice more than would be required with a longer barrel gun.
I bet it would be a good snake round.