JWZ found a site answering the question “How Hard Is It To Shoot Off A Lock?” Answer: Very, unless you’re using a shotgun slug.
However, we note after consulting with Senior Heathen Shootin’ & Lawyerin’ Correspondent Triple-F that the test is sort of stacked against pistols via round choice. A jacketed hollow-point or ball round isn’t meant to penetrate anything but, um, soft targets, whereupon it’s expected to expand. Rifle rounds are typically fully jacketed and NOT meant to expand, so all things being equal you’d expect such a round to go through more stuff than a bullet engineered for expansion. At the same time, all the rifle rounds used are smaller in diameter than the larger handgun rounds.
The test remains valid in a mythbusting sense, though, as movie gunmen would typically be loaded with “normal” pistol bullets like those used, not some armor-piercing round. (A bullet meant to go through stuff is less useful for stopping bad guys than a more traditional round.) We’re just curious about the corner case of a hard-alloy or fully-jacketed pistol round from a large caliber, high-velocity pistol.
Mostly because we’re very, very geeky. So geeky, in fact, that we sent email asking this version question. Watch this space for a follow-up.