First, those round shots really shed speed quickly. Plus the patterning, due to such a little load, relegates it to ten yards or so. You are saying it wouldn't even ruffle pidgeons at 12 yards? That's surprising as I should think even a light dusting of shot would annoy them. Then again, they're about the dumbest birds in creation. I just looked at your pix of the cartridge container and it says it will penetrate 1/4" of 200# paper at ten yards. What is 200# paper? I just checked some printer paper and it is only 20#, hard finish. Maybe that is what they meant; it will penetrate a quarter inch of printer paper. If so, it should have riled those birds and your pattern ought to have been just a shade over the six incher they show.
OK, just searched on the 200# paper. The 20# paper I refered to, above, weighs in at twenty pounds for 500 large sheets that are cut down into four letter sized sheets. That would make a ream of 200# paper weigh in at 50. Obviously, this isn't stationery. A further search found some post office packaging guidelines that mention 200#-test fiber board. Maybe this is a standard for cardboard? If so, it doesn't take much to punch through a cardboard box. Will research further........
For $200 it should do a lot better than that. And the shells are relatively expensive for a novelty. Look to see this one do a quick fade to black.
Yote (if you are the one with the hots for this gun): Ask around on the other airgun forums about some of the earlier shotguns like the Crosman 1100 (reloadable shells) and the Ye-Wha (sp?) which I think was a .25 Korean gun. The latter seems to have a fair power rep and is in the ballpark for what you want to spend. Also, there are Phillipines made airguns designed for actual hunting as they are severely restricted on firearms in that country. I wouldn't waste my hard earned dough on the Gamo. Let's just say that if a .22 springer shotgun is feasible, someone would surely have produced it by now. Gamo is just getting people excited and ripping them off. Same thing with the "bull" barrels.
What, me worry???