Here's an alternative that you may not find to be helpful or popular, but I'm just offering a suggestion. A decent alternative to Unique is Hodgdon Universal. It's not the same powder and the load data is not
interchangeable. But I believe it was designed to be a modern alternative to Unique. And it absolutely meters better.
It'll never be as popular. But Unique has a following and legend that far exceeds it's ability. It's a tired and over-used term...but in handloading, it seems like folks either love Unique or they hate it.
Typically, I'm a traditionalist in most things. Almost always in gun stuff, for sure. But not when it comes to Unique. I've been handloading a couple decades and the choices I keep in powder are, well, ridiculous. I keep on hand (and routinely use) a more dizzying array of handgun powders than any normal hobbyist has a genuine need or reason to do. It's like an addiction gone wrong.*
But I hate Unique. I don't like the way it meters and I can do anything Unique can do with different powders. In my world, it's completely unnecessary. And I do not say that specifically to annoy or anger the folks who love Unique
. As I said, I'm a traditionalist (usually) and I understand the people who love their "good old stuff." I'm happy it works for them and they have MORE of it because I'm not buying any of it.
*I currently have 15 different handgun powders (including Unique) and I regularly dip from at least 10 of those. That's nuts, I don't recommend it, but it is kinda fun if you like to goof around.