Salt risen bread cracking
I am trying to duplicate my grandmother's recipe for salt-rising bread. I can make a good starter and a good sponge. My finished loaves split, either on the sides or on top, or both. I knead the bread in a Kenwood stand mixer and I suspect I'm either kneading improperly or underproofing the loaves. I'm using about 55% hydration. If I add more flour and go down to 45%, I make bricks that sometimes still split on the sides. I knead the dough on a setting of 2-4. If I use a slower speed, the dough sticks to the sides of the bowl and turns into taffy! I'm typically kneading for 8-10 minutes.
After I shape the loaves, I'm filling my loaf pans about 1/3 full. I've been raising the loaves until double and have gone so far as to put some of the dough in a measuring cup to be sure I was really letting it double. Loaves still split! By accident I set my dough in the measuring cup aside last night and forgot about it. This morning, that sample had more than tripled in volume, making me suspect I'm still underproofing.
Any advice to this newbie greatly appreciated.