See, I never agreed with the whole "smaller air hole = no range change."
When I went to mod my friend's Recon, I hammered out the whole damn AR, peg ring and all.
So in simpler terms, my Recon had a probably 1/4 inch air hole and his had a 1/2 - 3/4 inch air hole.
His went 9 feet, mine went 47.
The thing is, the exact size of the hole doesn't make a huge difference as long as air is not escaping around the sides of the dart. Ideally, you want the hole to be the exact same size as the hole in the dart, but this is not always possible so smaller is generally better. If the hole is too small though, it will slow down the plunger.