Trinity is going to Super Game and we talked about a holder that would make it a little easier to store your FS. This is about as simple of a design that you can get.
I was thinking about modifying a feed tube off of the old Delta 68 pistol. That would make it a quick change tube then.
Whatever your hand finds to do, do it with your might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, where you go.