TexasCHLforum.com

The unsupported chamber concern with Glocks is most often directed at Glocks chambered in the 40S&W caliber. This caliber is more prone to pressure spikes and the Glock 40 Kb's failures usually begin at the unsupported area since that is the weakest point of the containment area. This, combined with some other reasons that I won't get specific on caused Glock a lot of problems several years ago. Many a Glock 40 bit the dust in the early 2000's. I know because I joined the Glock Kb club in 2001.

I do not think any of this is a concern for the Glock 9mm and 45acp. Prior to my Kb I was measuring brass from reloads fired in Glocks for 9mm, 45acp and 40S&W. The bludge at the base of the brass showed a much higher percentage increase for the 40 than it did on the other calibers. Unfortunately my research came to a halt when I had to take my Glock home in plastic baggies.