It has already been mentioned, but I'll reiterate:

Make sure you are talking about the correct "Clays" powder.

"Clays" is a very fast powder and is not equivalent to Unique. It really isn't even equivalent to Bullseye. It is no where near as versatile as Bullseye, in that pressure spikes much more quickly, especially with heavier bullets. For example, you can make full power 230 gr hardball .45 auto loads with Bullseye. I've never seen a Clays load in any manual can.

"Universal Clays", commonly just called "Universal", is very close to Unique, possibly just a tiny bit faster. It meters better than Unique, and I like it with jacketed bullets. .45 auto FMJ loads are impressively clean. Not so much with lead, it smokes a lot more. I haven't used it enough to know for sure, but I think it burns hotter than Unique, which may be burning the lube and causing the smoke.

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