I just returned from a trip to the woods to try out the shotgun and adapters. I was unable to use the local range (closed for maintenance) so I headed to a nearby logging road were there is a sort of unofficial target shooting area. Here is a brief report:
The shotgun in normal 12ga mode was very nice. It's light, handles well and the hammer, trigger and ejector all work very smoothly. I fired several 00buck (low brass) rounds with no discomfort. Then I fired 2 high brass BB rounds....well my shoulder and cheek are still a little sore as I write this about an hour later (I was warned that would happen). Overall I am very pleased with the shotgun. However, more padding on the stock is on the to do list for sure.
I had very low expectations for the .22 adapter (Short Lane Arms, 3" smooth bore) , I figured it would be a success if I could consistently hit a pop can size target at 10 yards. I tried a few rounds from a standing position at 10 yards into a paper target. The first group of 5 was probably 8". With some practice I was able to reduce this to an average group of about 3". The elongated holes definitely confirmed what others have said about "key holing" I also found getting a consistent site picture with just a bead front site to be a challenge. Once I had gotten the best groups on paper that I could achieve I switched to plinking at an old rusty spray paint can I found near by. With a little practice I was hitting the can 9 times out of 10. I found this more fun than I had expected. So I would say for close range small game, while not ideal, this adapter would be adequate (better than a slingshot anyway).
The .45acp adapter (also a 3" smooth bore) was less successful. I never achieved a paper group of 5 shots less than 8" at 10 yards. These were also key holing. When plinking I could hit a 1 gallon paint can about 7 times out of 10 (again at 10 yards). Other than maybe dispatching a wounded animal at point blank range, I can't think of many practical uses for this adapter.
The .410 adapter report will have to wait for another day, since I have not picked up any .410 ammo yet.