Don't be afraid of the buckshot, If I still have a tag to fill late in our gun season I go pro-active and jump shoot deer off the end of my boot. I've used this method often and succesfully with a specialty choke. It's called a PatternMaster. I couple this with 2.3/4 OOO because it flys faster than 3in or 3.5s and can be devestating on deer. Most never get out of there beds, but I've dropped them in there tracks at 60yds. Those are 36 cal. balls your throwing out there and it only takes one but that's rarely the case. Like others have suggested you have to pattern your gun and try different chokes and shell manufacturers to find what your gun likes.
Just use bigger buckshot than those little 000B!
Below: Comparison of Dixie Tri-Ball buckshot (.60 caliber/325 grain pellets) with an equal weight of 00B (.33 caliber/54 grain pellets).
Patterns with Tri-Ball run < 6" at 40 yards with a full choke.