FatChance: There's been intermittent discussions here about these kind of loads--try searching this forum (use google) on such terms as "FBI800," "38+P 158LSWC-HP," or the like. Several of us have worked on these loads as well--in both 38, 38+P, 38 CIP, 357 Magnum, and even sorted out '357-lite' loads for them.
Other than the Zero bullet (which may be an import, right?), and possibly a cast one from Tennessee Valley Bullets(?), the only 158LSWC-HPs around are those from Speer or Hornady. However, based on my experience, one can readily develop a load using the traditional 158-gr. LSWC bullet. FWIW--the Speer / Hornady bullets are similar; both are swaged. Because of that, they will strip out and lead horrifically if driven much over 900 fps. The ubiquitous 158-gr. LSWC is available in various BHNs (there's another discussion going on about that right now), and probably work as well for barrels beyond 4" as the swaged -HP variants.
A current-pressure / current data 38+P load in factory ammo will run about 800 fps from a 2" barrel. The best velocities in shorter barrels seem to come from not the fastest powders, but from 'medium' powders--in my experience, AA#5 or Ramshot True Blue. Another powder some like is HS-6. With the right powder, that 3" barrel should get you close to 900 fps--which is even a bit faster than the original 'FBI load' did with their two-and-a-half-inch barrel.
Good luck with your interest; I've enjoyed doing it, too.
Jim H.