cpobb: I reloaded for this cartridge before it even became the 400 corbon. One good load for this 400 caliber that you can hunt with, play with or defend yourself with is the 180 grain RCBS semiwadcutter slug. When cast soft over 4.3 grains of WW231 she is a more accurate target load that I've shot with my 45s. With 6.5 of Unique and a harder cast she is an excellent plinker and defense round at about 1100'/sec. With any other full powder charges (SR 4756, Blue Dot, more Unique and now probably some of the VV powders) and the bullet cast hard, she is a great game round at the sam level as the 41 magnum.
All Corbon did was to take a cartridge case that had already been designed and drop the bullet weight to the flying ashtray level. I always thought the Elmer Keith notion of a 40 caliber with a 180 grain bullet at between 1000 and 1200 would make an excellent Police and field load. Hope this helps. Mikey.