On my thread in Concealed Carry sub-forum, I have been pretty well convinced that any side pocket carry of an S&W "J" frame or Ruger LCR in Bill's Khakis that have not been substantially altered will be unsatisfactory.

I had a Hume 715 IWB holster that was superior in use but for one small detail, that of the S&W 640 falling on the floor when I dropped my trousers on the toilet. I got the holster from my "stuff" bin to attempt to reshape it to fit the LCR, for my 640 now belongs to a close friend who helped me recover from having had five cervical vertebrae fused.

My first conclusion was that there is no way my LCR can fit the holster because of its exaggerated trigger guard. I soaked holster in warm water for about an hour. Having sealed the LCR in a Zip-Loc bag, it took nearly 30 minutes to insert LCR into Hume holster. Between hands grasping holster leather, plus my subsequent use of a toothbrush handle to "bone" wet leather to better fit LCR, I did what I thought couldn't be done. The holster is dry. It fits snugly enough that the 4+ ounce lighter LCR doesn't drop from it when holster is turned upside down and modestly shaken.
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Okay, to my question. If the water soak and 30 minutes of manipulating wet holster to a significantly different shape has affected leather's shape retention or anything else detrimental for the holster to have a long useful life, what do I do to have my resurrected holster stay resurrected and useful?

Your treatment will have had an effect on the holster's finish, probably removing any sealant completely. Recommend that the leather be sealed to protect against moisture infiltration.

Leather craft shops will have finishes and sealants that will do the job, such as Fiebings Tan Kote, Bag Kote, and others. Prices for small quantities are a bit high, though, so you might want to look around in your cabinets to see if you have any Mop-N-Glo on hand (a pretty good water-based acrylic sealant).

Avoid any solvent-based products. Avoid any oily or greasy treatments. Two or three light applications are better than a heavy dousing.

You now have the best information you can get, and the thread can be closed.

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Stay protected my friends.

Many thanks for your reply. I'll go to Missoula Friday.

I found a hand-labeled plastic bottle of leather sealer on a storage shelf. I seem to remember receiving it from the saddle maker who made two knife sheaths for me.

The liquid is white, thinner than skim milk, and does not adhere to bottle's wall. It has no smell, so I am nearly certain it is not solvent based.

Please recommend a method for its application, also drying time for each application. Possible application methods I have come up with are: artist's camel's hair brush; saturated paper towel; Q-tip; transferring sealer to non-pressurized pump bottle and "spritzing" it on. While I suspect I'm overthinking method of application, asking cannot be a mistake.

Don't know what ya got in the bottle there.
There's different ways that people apply their leather finishes. Some use an air brush, some a damp sponge, others use a dauber.
I use Fiebings Tan-kote as a top coat.

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Keep on Chooglin'

Last application of leather sealer will be applied this evening. I will wear it beginning Sunday.

Within a week, I'll report the efficiency of this reshaping/conversion, the important features being whether the apparent "toggling" effect that locks LCR into the holster disappears with holster's use, and revolver retention upside down. I might be identifying the same feature slightly differently.

Okay, I've been wearing the LCR in the [its!] Hume 715 holster. Parenthetically, the holster affixes to belt with loops-and-snaps rather than spring clip.

1. The toggle effect I described disappeared within a day. Reshaping the water-soaked leather appears to have shrunk the leather. Boning the leather to a form fit appears to have hardened the leather. There is no "slop" in the fit because of LCR's smaller cylinder. I believe most of the "slop" disappeared because of the LCR's larger trigger guard - that is, holster has been forced to be more naarrow (top to bottom when LCR has top strap on top) by the trigger guard seam being stretched. This stretch is so dramatic for leather and, especially, stitching that LCR's trigger guard is almost "captured" by reshaped leather around seam.

2. I placed four applications of leather seal furnished by my saddle maker in five days to the leather. I am uncertain whether this leather contributes to the leather's hardness and strong grasping of the revolver. Tightness of fit to holster, perhaps in tandem with less weight, weight being distributed forward of grip, has translated to the revolver being 100 percent resistant to inadvertent dropping from holster.

If I had to bet, my bet would be that, because of LCR's trigger guard forcing forcing stitching where leather meets it, this holster will not become a sloppy fit for many years. Therefore, thanks to snubbyfan and LoboGunLeather, my holster's resurrection is successful.