Can actually agree that explosion radius is quite large.. it does damage nearly twice as far as the visible explosion. It has since the barrels were editted some time ago (remember they stack-damaged for awhile, 3 of 'em insta-killed you).
It's much more pronounced now that frags were upped and usable, you can get bled a mile away from the actual explosion. Also the explosion weapons can bounce you around and dominate small areas.
I'll see about the radius, but explosions aren't going to be removed, lol.