Waldog.
You want to be careful with the !!mm they have a groove diameter from .436-.464.
I dont know which 11 mm you have .43 Spanish, 43 Mauser, Turk, French, Beaumont had a lot with the 71's so be careful.
Yes you can patch a GG bullet as long as you don't over size it.
A over sized PP bullet will raise the chamber pressure as much as a jacketed bullet will.
The 71 Mauser is not a strong action so be careful with over sized bullets.
LP.