Wild Bunch specifies large calibers and has a minimum power factor.
Many of the top competitors in my Cowboy group shoot 38 Special loads while others shoot 38 Short Colt, 44 Magnum, 44/40, 44 Special, 32 S&W, 32/20, and 45 Colt. The black powder folks generally shoot 44/40 or 45 Colt. I usually shoot 45 Colt, 44/40, or 44 Magnum in both rifle and revolver even though I am set up for 357. I frequently shoot a Marlin 32/20 rifle made back in the 1800's and would have a hard time making much of a power factor with it.
We shoot for fun and bragging rights (nobody wins a new car) and welcome folks shooting a variety of chamberings in a variety of categories. Someone generally brings a 22 rig in case any youngsters want to give it a try.
