[Shadow9mm]

I have heard titegroup and lilgun will both leave the gun warmer than most after a few firings. As well as that lilgun can cause premature erosion and or wear. I cannot say for tite group, but lil gun does warm the gun up pretty quick. Although I have not seen the erosion they talk about.

If it's a 2in gun with titanium cylinder it may be unpleasant to painful to shoot with full power 38s and 357s, just fair warning.

Based on the powders you have I would start out with hp-38 or unique and see where you wind up. Both are good powders with good reputations for working well in 38spl. I would not go any slower than that though. Based on my tinkering so far it seems that with full charges of slower powders you may get a bit more velocity, but just be wasting some of the powder.