Jag, I use the short version 'cause the barrel is chambered for shorts. Have shot some of the CB longs but have not found the precision wanted. They would probably work at the ranges I swat pigs at, but.....
CB shorts checking zero after a thorough scrubbing...on the 25 yard line, elbow rest:
LR Quiet at 20 yards from a "real" gun and this is by far the best group I've ever had with them. CB longs do about the same for me in a LR chamber.
Same chamber with LR SV ammo:
My original purpose in having a short chamber was for hunting squirrel. I've had some success with that, but with a different sort of ammo....
The BB Caps are the schizzle for bustin' tree rats inside 30 yards or so. 'Dillos and other pests as well. A curiosity I've not sorted out is why the BB caps kill 'em quicker than the CB caps. I'm not thinking that hydrostatic shock is the answer....