For those that would like the opportunity for a little more variety in their TSHTF pistol arsenal consider the Lone Wolf Distributors Glock Conversion barrels. In my case I have a Glock 22 (okay a couple) and wanted the opportunity to fire the cheaper and in some locations more popular 9MM, the $100 Lone Wolf Conversion barrel fit the need nicely. Granted my experience with pistols has only been .40 caliber but it was exciting to put the 9MM barrel on and see shots were grouping closer (12"....jk) and obviously quicker due to the reduced recoil of the 9MM. These are the standard 100 count Target/Range WWB from Wally World but I'll be upping the ante soon with some more powerful 9MM rounds. Some of you may be die hard .45 guys, which I understand and respect, but the ability to convert to multiple calibers in a single, durable firearm within a few seconds and at a reasonable price was a big bonus. They do recommend you switch to the Glock 17 magazine as well which I did but I seem to recall some guys doing it with the G22 magazines. If you have a Glock 20 (10MM) you can buy the conversion barrels for .40 and/or .357 as well. Too bad they don't make the Glock 21 able to fire .40, 9MM and the standard .45, that would be my ideal range of calibers.