FWIW, back in the day, Lee would install a dot of any size the customer wanted - larger for brush guns, smaller for targets & long distance.
Some scope companies, like Lyman & Weaver, had only certain sizes available, depending upon scope magnification - but anyone could send their scope direscly to Lee for a custom installation.
I've had a Weaver K4 with a fine dot forever, I never bothered to measure - since the dot virtually represents a .22 cal bullet hole, at the distances I hunt tree rats with the rifle it's mounted on.
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