Weighing up calibres

I use a 20-bore to shoot pigeon because of a shoulder injury. Is this smaller calibre disadvantageous compared with a 12-bore when it comes to range?

Peter says: If you are using a 20-bore because you need a lighter gun due to your shoulder injury, then that is fine, but, as far as recoil is concerned, if you put a heavy load through the 20-bore, it will kick more than a light load through a heavier 12-bore. Put simply, if you can manage the weight, a 24gm load through an 8lb 12-bore will give you the least recoil without compromising your killing range.