I've never tried the pellets so I can't comment on those.
I get my bullets from Midway or I cast my own, the ones used on this group is Oregon Trail Laser-Cast .356 147gr.
http://www.midwaynorge.com/apps/epro...eItemID=446094
Precision is also good with the .360 roundball.
http://www.midwaynorge.com/apps/epro...eItemID=714224
Hunters supply bullets should also group well.
http://www.midwaynorge.com/apps/epro...eItemID=838992