Zen21Tao
Member
So, first of all I love .40s/w infact my next gun purchase will be the Springfield XD in .40cal, an old timer told me that a .40 was a necked down 10mm because 10mm is a propriatary caliber owned by Glock. Reading this thread I think he may have been wrong but I still have only seen 10mm in Glocks, does anybody else make 10mm guns?
Look up at my post. In addition to my Glock 29 10mm I have a Kimber Stainless Target II 10mm and just bought a S&W 610 10mm revolver. Other 10mm include the Colt Delta Elite, EAA Witness, the Bren Ten, Dan Wesson Razor Back, and a number of S&W models.
Here is a link with many more:
http://marina.fortunecity.com/harbour/347/10mm06.html
Here is a link with detailed info on the creation of 10mm:
http://marina.fortunecity.com/harbour/347/10mm01.html
The .40 isn't "necked down." The 10mm and .40S&W both use a .401 diameter bullet. The casing for the .40 is just a little bit shorter than the 10mm's casing, much like the .38spl and the .357 magnum. The major benefit that came from using the slightly smaller .40S&W casing with less powder charge than the 10mm was that the 40S&W could be designed on a 9mm platform frame. This resulted in a round more powerful than 9mm (in many cases close to .45acp) with a magazine capacity almost as great as the 9mm.