Hi Madcarlos
I'm not an expert, but the guns that seem to be reccomended for IPAS (Iron plate action shooting) at my club include the S+W revolver - perhaps best with the 6 inch barrel - the colt 1911 and the CP88. I have got a beretta 92 which also seem fine - it shoots reasonably straight and the trigger doesn't feel desparately different to some of the others, and I have had no jams (except when putting in the magazine back to front - a one-off mistake!). But I don't think any of these popular reproduction CO2 guns come anywhere near the 6ft/lb power permitted for handguns - I think they are nearer 1.5 to 2 ft/lb
I seem to remember crosman or brocock do a full power CO2 pistol but it isn't rapid fire.
Sorry I don't have more info
Jon