4006...
 

After talking with Excalibur, I went through all the pages that claim the 4006/4046 is featured in the film, show or whatever. With the exception of Catwoman, 24 Season 3 and JAG, which were not confirmed 4006/4046s but just inconclusive, I saw no 4006/4046s in any of the movies/shows/whatever and no evidence that could convince one to believe that they were 4006s over the 5906/5946, and changed them accordingly. Just letting you all know if anyone is curious as to why a bunch of random pages got edited, or if you want to discuss it.

I've been skeptical myself. .40-caliber handguns in general are rare in movies and TV shows compared to 9x19mm. If you can't tell whether a handgun being used is a 9mm or a .40, the safe bet is almost always 9mm.

Exactly, but on top of that, there are some subtle differences that one can point out to distinguish a 4006 from a 5906, or from a 639, 659, 4506 or any of the other S&W classic autos. None of the guns I've seen meet the 4006 criteria, though the one in JAG might, but I still believe based on the 9mm argument that it's a 5906 there too.

I must point out that there ARE .40 cal pistols in movie armory inventory, FEW, but they are there. For example, one of the ones I photographed was from CW and the other is mine. Sometimes productions are very specific as to what gun they want, usually because the director has a preference. It is rare but it happens.

I prefer yournamehere's criteria in which he specifically looks for physical details over just assuming that the gun is a 9mm. If the gun looks like a 40 cal, there IS the possibility that it is. Don't eliminate it just because the 9mm is more common.

The thing with .40 cals is most of them look exactly the same as their 9mm counterpart save for markings, which are almost never seen. I think it's best if we really look at a gun and see if it has any subtle features that make it a .40 caliber variant, but most of the time, it's not possible, like with SIGs and Glocks. They look about exactly the same. In cases like that, we should assume that they are 9mms, unless there is actual evidence otherwise, but in the case of the 5906 and the 4006, where there are physical differences that are pretty easy to note if there are good screenshots and someone who knows the differences, it's provable one way or the other.

Another problem is all the cool kids who come onto the site who think that no person (fictional characters, mind you) would EVER use a "pansy ass 9mm", and so if there is a variant in a better claiber that looks the same or similar enough, that HAS to be what is being used, but that logic is completely nonsensical in terms of film.