John-

I shoot roundball in both of my 16b double rifles.
16b roundball = 1oz

I have yet to chronograph either of them. I've tried a few times, but I'd been having problems with my chronograph (a PACT, it wasn't getting signal from the start screen or some such crap...)

They shoot well, recoil isn't an issue at all. From the sound of the rifles, and the relative quickness of the impact into the 120yd berm, I'd say they're working up fairly decent velocity with the 2-3/4 dram FFg charge I feed them.
The lighter of the two will blow a 5gallon pail full of mud to pieces at 30 yards.

On the way to getting them ready to shoot, I'd discussed the matter to some great extent with Lewis Drake and Ross Seyfried. Both of them had hunted with similar charges behind 16b roundball. Mr Drake said he'd taken numerous bear with one of his 16b roundball double rifles and had hunted with it for decades.

I can't think of many game animals on the North American continent I wouldn't feel comfortable hunting with them.

I'm looking to possibly take the heavier of the two on a bear hunt in September.
Expect some type of range report before then as I need to finish some cartridge development for it and also need to chronograph it before I decide on whether or not to hunt bear with it -- just want to know what it's *really* doing if you know what I mean...

Here's a picture of the lighter of the two, a seven pound 16b double rifle.
Likely good enough for the job of hunting coastal black bear here in California.
Although a pinfire gun, of a forward-facing underlever design, it's a jones-type dual opposed underlug locking gun, in almost as-new condition. It's tight and on-face with perfect bores.
This image from it's first time shooting in very likely over 100 years.

This image of the heavier of the two, in it's case with tools and such...

I know many of you have seen these images here before, I hope to some time soon get around to setting up and photographing them to greater extent for this site's photo archives.

Oh by the way, Daryl's 14ga (14ga being bigger than 16ga) is set up for a much stiffer charge than my 16b double rifles.
His is actually much more 'oomphy' than my rifles and has been reported to send roundball completely through very large Canadian Moose, flattening them in their tracks.
I've heard of 16b double rifles which were also set up to take much heavier loads than my two rifles were regulated for.
The lighter the rifle, the lighter the regulation load.
I can imagine three and a half to four dram guns weighing in at around 10+lbs

--Tinker