spring loaded and concealed

[auxprix]

I wasn't sure where to put this thread, so to "General" it goes...

Before I ask, I want to make it clear that I do not plan an manufacturing such a device and using it (I'm not stupid). It is just a mild curiousity that has arisen from Movies and such.

I'm asking about these spring loaded concealed weapons. Things like guns and blades that are somehow triggered out of a persons sleeve (usually attached at the forarm) or boot without a visible triggering movement. You see contraptions in films like "The Taxi Driver" "Marathon Man" and "Hellboy" (Bad example, I know) as well as the Bond franchise, where that woman had a poison blade in her boot.

My question is: Do these contraptions actually exist? Are they manufactured somewhere (like, in some other country) or mainly makeshift? Also, if they do exist, How does the triggering method work and what keeps the weapon from being mistakenly drawn?

If anyone has any insight, please let me know. Again, just curious.

 

[Touch Of Death]

Of course they exist, but you gotta wonder about the type of person that walks around with pistols up his sleeve. I know a true story about a guy that walked into a martial arts school and kicked at one of the students. The student was yanked out of the way just in time, and the guy with the shotgun in his boot don't walk so good anymore.
Sean