It does 2500fps with 200gr (verified data)
Likely 2700fps with 180gr (not tested though)
This is the equivalent of the .358 Winchester, easily.
It does this at relatively low pressure. With a case as big as the .348 Win, bolt thrust becomes enough of an issue to start being the limiting factor. The internal case head diameter is slightly larger than the .500S&W which I used as the bench mark. Using medium powered 50K psi loads for the 500 S&W, I was able to maintain bolt thrust numbers if I keep the .358 Craig at around 44K psi. This keeps the barrel lug from being battered and becoming loose (at least that's the plan!).
In something stronger, like a falling block or Siamese mauser, this round has alot more horsepower, easily equaling the .35 Whelen. Running that power level in a Handi wouldn't be something I'd recommend though. The whole point to this exercise was to develop a relatively low pressure round that won't be abusive to the break-open Handi platform while also providing a serious step up in power and range over the .357 Max. AND do it within the 1.8" length for the new Indiana deer laws (hopefully approved soon).