But it's dependent on your point of few. Some of it comes down to cash flow. Say I'm a .40 S&W shooter and I want something more powerful.
Do I purchase a 10mm or a .45 ACP?
True - however - I'm not a .40 S&W shooter.
I am a .45 LC shooter though.
.452" 230 grain lead bullets work in both .45acp and .45LC in my guns.
I got "lucky" w/my Blackhawk .45 Colt.
The bore and chamber mouths all slug the same - .451".
I've also got a Winchester Trapper in .45LC that eats the 230 grain like candy.
Pretty much the same as your method.
I stock one "standard" bulk for both for "plinker" or "shoot em up" rounds.