Instant 22: Rimfire conversion kits for Glocks
One of the great things about the Glock platform is that, with the possible exception of the Colt 1911-series pistol, they have just about the largest selection of aftermarket add-ons in the world. Besides performance and cosmetic parts, there are also sub caliber kits that can drop the chambering down to something a little…less.
Simply put, these conversion kits swap take your standard Glock pistol, and after swapping out the loaded slide (which includes the barrel, and recoil spring/rod) and magazine, will then shoot .22LR ammunition. As such, as long as you can field strip your gun for cleaning, you can install one of these kits on your frame. Then, when you are ready to return the gun to its original caliber, just perform the same procedure in reverse, as it creates no permanent change to the Glock.

Read the rest in my column at Glock Forum.com