Trappers in AB can get a ATC while only on their line. Prior to this year the calibre carried was for protection only and therefore had to be sufficient to do the job. This year, the ATC was extended to smaller calibres that can now be used for dispatching and so now a .22cal. could be used. Only one handgun can be carried at a time. There was never a restriction regarding muzzle velocity, not here in AB, who knows what they do in the province that enabled the long gun fiasco...
PS... Keep in mind the applicant still has to jump thru a lot of hoops to obtain this ATC and should have a very clean nose..