I need to re-visit wadcutter loading. I qualified with the old carry ammo in my S&W M-642 a few days back, and those 125 grain +P loads buck just a bit in that lightweight thing. HKS speed loaders are a PITA with the Pachmayr grips, too. The Pachs make the revolver fit my hand better, but they need a re-contouring to give some wiggle-room for the loaders to do the right things. Another case of S&W stuffing too much cartridge into too little platform.
First World problems, yeah.
I don't know which Pachmayr grip you're running on that 642 but I hear you loud and clear on the issue.
I've always found the S&W DAO J-frames to be excellent tools but when it comes to concealable grips, there's always some compromise involved. In order to preserve the ability to conceal the gun (particularly in pocket carry) the grips need to remain fairly small. For me, the grip cannot extended beyond the backstrap or the butt of the grip frame. I've had good experiences with Eagle Secret Service Style grips (yet another copy of the excellent Craig Speigel "boot grip").
A Tyler T-grip adaptor added to an old wood factory grip is also a Speedloader friendly option that is still small enough to be concealable.
Just a side note here; I received a message from Tyler Manufacturing. A family member had a severe illness, so they're struggling to fill orders right now.
One of the features of the Eagle grips made of Rosewood is the wood is the same color all the way through. You can file/sand them, apply a little Linseed oil and the finish is right back where you started.
On the issue of Speedloaders, don't forget the old Bianchi Speed Strip. It's not as fast as a speedloader but it is flat and easily carried.