But why? I have a Browning 1910 in .380 that has a bore that shows portions of rifling in between the craters and it still groups well at 21 feet. By grouping well, I mean 3-4" with no evidence of tumbling bullets. Yes, I like my bores to be bright and shiny with crisp rifling but given the "purpose" of such a pistol, it is satisfactory as it is.
However, I think it would be easy enough to do but I would include the chamber in the reline. Maybe even increase the length a few inches.
.380 ACP is a whole different horse. 21 feet (I have two Walthers in .380 ACP. 9mm "Kurz") is about triple the distance at which that belly-buster round is at its best.
Yes, they can print well-enough at 25 yards. But the round doesn't start with a great deal of kinetic energy, and loses what it has rather more rapidly than its "cousin" - the 9 mm Parabellum.
If nothing else, the .25 ACP is unpredictable.
Sometimes.. one round is lethal.
Other times - and I KNEW both parties involved, Rappahannock County, Virginia - shooter "A" puts an entire magazine of .25 ACP into "B" at arm's length, gifting "B" with a permanent limp from a damaged hip-joint, but no noticeable effect but bloody trousers for nearly an hour. Yes, strong drink was in-play.
"B", unarmed with anything other than greater body-mass and heavier bone-structure, meanwhile barehandedly gifts "A" with a smashed skull that left him with a silver plate to cover the damage ... after he came out of the coma. Even so, he was never QUITE right in the head, afterwards.
All a piss-ant handgun of that sort can be counted on is to get a person into more danger than it can get him OUT of.
And a .22 rimfire was always cheaper to plink with.
More deadly, too, for whatever THAT might be worth.