albertan,
Thank you for the reply.
I was hoping to know about actual velocity of the factory load, fired through a production gun.
We are experimenting with a lightweight 200 grain, 12 ga slug and received 3000 f/s, loaded in 3" hulls.
Since the 338-378 WM with a 200 grain bullet is the fastest factory cartridge with such a bullet weight, I was thinking if we could reach or surpass its velocity using 3.5" hulls.
I agree with you about muzzle brakes. Don't like them either. But, a 200 grain slug at 3000 f/s from a 7.7 lbs Benelli Nova shotgun does not kick appreciably, I would say.

Lefteris
www.europeancartridgeunlimited.com