No the guns that I looked at at the time cannot interchanges the rounds.
Has anyone fired the Glock 37? Is there any difference between the .45 ACP round and the .45 GAP when firing? How is the selection in buying .45 GAP ammunition?
Thanks for all the feedback. Future availability of the round was one of my main concerns with the GAP. The Glock 21 is a little bulky IMO; what I'm going to do is rent a Glock 22 and Glock 21 from my local range and fire 50-100 rounds through each and see which is preferable. I'm already leaning towards the 21 buy if the 22 wows me maybe I'll go that route.