Here is something from lone sentry on penetration.
http://www.lonesentry.com/ordnance/3...k-grenade.html
One was statically detonated against the face of 7-inch homogeneous armor plate. It penetrated completely, leaving a hole 2 1/8 inches wide at the face and 1 1/8 inches at the rear
For range there is this,
Terry Ganders book German anti tank guns 1939-1945 says the stielgranate has an accurate range of less that 200m but later on in the book a picture caption says it is effective only at short ranges-about 400 yards maximum.
I am curious as to why the PAK stielgranates cant have their normal HE and AT ammo as well as a few stielgranates? In Terrys book a picture for the gun clearly shows it with a stielgranate on the barrel and normal 3.7 rounds all around the gun.
a cropped version of this picture is available here
https://weaponsandwarfare.com/2015/1...7-cm-pak-3536/