I think you would want to limit your shots to no more than 75 feet( 25 yds.). 60 feet( 20 yds.) is more like it. Sometimes you simply have to wait for a squirrel to come down out of the high branches in an Old OAK Tree, or a Walnut, or Beech tree, to get them in range of your shotgun. But, then, isn't patience the core characteristic of Squirrel hunting?
You want a load that will put #6 or #5 shot in a 20 inch circle at 25 yards that insures hits on the body the size of squirrels. The Weight of the pellet is the key to pellet energy, altho at these short distances( under 30 yards) you don't lose a lot of energy or velocity from the MUZZLE. You can kill a squirrel with a centered pattern of #7 1/2 or #8 shot, but I recommend using #6 shot as a minimum, particular when shooting at a squirrel more than 25 yards from you. For all squirrels, #5 shot speaks with authority and carries a lot more energy to the game animal. The Shot tends to penetrate completely through the squirrel, so you don't have to " fish" for spent pellets in the meat. :thumbsup: