Wadcutters work exceptionally well on small game provided you can maintain sufficient accuracy (dime- or nickel-sized groups for gray squirrels), and that you have adequate velocity to ensure penetration. 400fps minimum, and preferably more like 450fps at the point of impact. An unmodified 1322 will be marginal so I strongly recommend testing penetration with a fresh kill at whatever will be the max range. If the wadcutter does not make it to the hide on the opposite side, try a dome instead.
For example, here's a brief clip that I recorded a while back demonstrating how effective a low power airgun can be with proper shot placement. In .177 cal, this wadcutter arrived at about 470fps (4.6fpe) and hit the off switch. As stated in the clip, it's intended not as a recommendation so much as showing what is possible. There is very little margin for error. For example that would have been a no-go if I had any wind to contend with.
https://www.youtube.com/watch?v=TMC04JPmWns
FWIW, my preferred 30yd squirrel rifle these days is a QB79 HPA conversion running the same RWS Supermag wadcutters at about 14fpe at the muzzle (vs only 8fpe for the video). It's unusual to find wadcutters that group well at that distance at any velocity but this is one of the exceptions. Given the fact I stick almost exclusively to brain shots on gray squirrels, a wadcutter doesn't really offer me any benefits for that purpose but they are very effective for center mass shots on smaller targets like chipmunks and house sparrows that show up.