Something else to consider when testing defense ammo is bullet pulling. This is when bullets are pulled out of their cases while the gun is firing. If they come out far enough, they can lock up the action. I experienced this with 158gr +P ammunition in an 11oz. J-frame (not bad enough to lock up, but very visable).
You can test this by loading all chambers with defense ammo, and firing 3 rounds. Now open the cylinder and examine the remaining rounds. Compare them to additional rounds that were not in the gun. Close it and fire the 4th round, and examine the 5th (assuming 5 chambers total). If it has pulled out at all I would probably select a different round, but if it only pulls out a tiny bit you might consider that acceptable.
Besides causing malfunctions, bullet pulling can also change the pressures the cartridge will achieve, which may be dangerous for the gun and/or cause the hollowpoint to not achieve the needed velocity to expand.