I have the 20, 23, 25, 27, & 30 grain spouts. At 30 grains there is no room for a lube wad under the conical. I like 30grs when I need a "thumper" to tip over a big faller. The conicals shoot higher than the balls. I'd start at 20grs and work my way up to 30. I smear BP lube into the groves of the conicals.