A .30 carbine will penetrate completely an old creosote covered telephone pole, it does have penetration, I talked to Corbon and Hornaday many yrs ago about making and XTP bullet for it and Corbon beefing it up a bit, but alas no action, although they were both interested. Hard to find these days, but a friend of mine was working on loading the sabot Remington bullets in .30 Mauser/Tokarev in theory, a 45 -50 grain .224 bullet in a sabot, would do over 2k fps, still has not scienced it out. But good idea. This would be out of a Tokarev or Broom handle mauser.