My home made set does not have the split down the side. But if the empty swells it is a real bugger to get out sometimes. The store bought set does have the split down the side. I use the home made set most of the time. Federal Paper hulls work well for me and I have thousands of them.
Even if I did not, it is still far cheaper to loose a 12 empty each time, due to a split, than to find a large supply of 10 empties. I use to think 28's were hard to find but they are common compared to 10's. At most skeet or trap ranges you can get all the free once fired 12 ga. Remington Gun Club or AA empties you want out of the trash can or off the field. Load them once and throw them away.
