I got a SIG-Sauer P227 in .45 ACP, and with it, a Mitch Rosen holster. Mitch Rosen Extraordinary Gunleather is located in Manchester, New Hampshire, and has been in business since 1991, but I had not encountered their work until I visited the SIG-Sauer Pro Shop in Epping, and boy, can you drop a bundle in there.
Mr. Rosen makes what you might call minimalist holsters. He has half a dozen styles, but none of them use any spare leather at all. They are compact, hug the body closely, and hold the handgun very, very tightly. This presented a problem, as my new holster would not let go of my new P227 short of using a dragline, and getting the SIG seated required a triphammer. All good holsters fit this way.
There are a number of cures. The least desirable, in fact the one you don’t want to use at all, is rubbing oil, silicone, graphite, or anything else into the interior of the holster. Anything that will soften the leather is BAD, as the holster will quickly lose its grip. You can put the plastic bag the holster came in over the gun, shove it into the leather, and leave it overnight. This works, too, I am told, as does wrapping the gat in Saran.
But by sheer accident, on a search of the Internet, I found what might be the best method of all, courtesy of a gent who calls himself Deputysherrif100. Take two sheets of wax paper, wrap them around the parts of the pistol that go into the leather, shove the gun in, and leave it overnight. Keep the waxed side toward the leather, not the gun. This process stretches the hide just a tad and leaves a tiny amount of wax, but not enough to soften anything. (It also keeps your gun from spoiling.)
If one treatment doesn’t get things where you want them, a second one surely will, and then leave the handgun holstered for a couple of days, minus the wax paper.
Soft leather works well for some applications, but holsters, climbing boots, knife sheaths, and saddle scabbards should be as stiff as boards, and anything that makes them less so should be kept on the other side of the room.