Erich, you should check out Handloader #243 for Pearce's article on 38-44 HV loads. There are a few 38+P loads there but no mention of 2400. However, there are a number of 2400 loads in the 38-44HV table that yield some pretty impressive velocities. An advanced handloader should be able to extrapolate from those starting loads and current manual info for 38SP loads to arrive at something interesting
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I have to admit, since the 38-44 thread a couple of weeks ago I've been working on some 38-44HV loads to use in my SP101. No particular advantage over the 357Mag in that gun ... except it may be easier to eject empties as well as carry and load them from a Speed Strip or HKS. Could be interesting in some properly rated J-frame +P level applications.