bending with index

can you bend a full step with your index finger?
i cant, and if i try it hurts.

Blues Shredder

Not something I have done before I read your post, tried it and , well it works on some strings at variouse parts of the fret board and found it easier to bend down from the thumb at the neck end but not much trouble from fret 5 and up, but it could and will depend on the size and strenghth of each guitarists fingers and technique. I can bend a full note with my little finger un aided by the others, but then all guitarist can, probebly.

Riff and be merry

The brand of strings you have and what gauge you have make alot of difference in how well your strings bend. Maybe if you use a lighter set of strings it will work berrer for you.