Looking at what all's been said in this thread, I would suggest a likely explanation could be, 30 degree dive in to a point 100-200 yards short of the tank, pull levelish, line up shot, guns hot at 50m, pull up?
Wiley.
The guns were fired at 30°, because that gave a resulting strike angle of 90° for maximum penetration (due to the sloped T-34 armor):
(Pegg, Simon: HS 129 Panzerjäger. Classic Publications, 1997, page 80)
However, i have some troubles with the pilot's claim stated in the same book (page 182):
"We would normally open fire at a distance from the target between 45(sic) and 60 metres, and from such a close range the 30 to 45 degree diving angle brought the plane dangerously close to the target"
And this would be
dangerously close indeed. Even at a slow 200 mph (360 km/h) dive 45m means there's 0.5 seconds left to impact. I can imagine frantically pulling up at that last split second, but
opening fire at that range, shooting a few rounds and
then pulling out?
I have serious problems to understand how that could work...
Addendum: Just did a few test in the Ju-87G. I couldn't even dive that slow... more to follow