Huh?
You can match just about any velocity with 3F black powder that you can achieve with almost any smokeless shotgun powder. Sherman Bell has published several. Just by looking at the 10 gauge loads listed on the Parker forum there are heavier (1 1/4 oz) loads of around 1300 fps.
You could easily achieve even higher velocities (if you felt the need to) with lighter shot loads using the same powder charges.
In his series of articles he did 12 gauge testing as well, but I am not about to rifle through old articles to find them at the moment. Sherman Bell did point out though that modern black powder shooters are much too conservative in their loads. Using stout charges of 3F "sporting" powder such as Swiss, more closely matched the powders and loads 19th century shot gunners were using.
It's not for lacking velocity as to why black powder fell out of favor.
