The recoil of my 75B is quite mild even with "hot" ammo like Hirtenberger 100gr +P+ JSP
Interesting! The Hirtenberger is the only load my 75B wouldn't feed reliably.
Were you using the 100gr JSP or one of Hirtenberger's other loadings such as their 124gr FMJ? The 100gr JSP ran flawlessly through my gun though, admittedly, I only shot about 30 rounds of it (I've still got the remaining 20 rounds out of the box part of which is shown in the picture I posted).
My experience with reliability is similar to yours in that the only loading that's ever given me trouble was a single round of Silver Bear 145gr JHP which had an OAL so long that it stuck in the chamber requiring the gun to be very carefully disassembled in order to remove it
Everything else I've shot including exotic ammo like Glaser Blue, Cor-Bon 100gr Pow'R Ball, Hirtenberger 100gr JSP, Fiocchi 92gr EMB and more conventional JHP and FMJ loadings from 115gr to 158gr have all fed just fine.