I re-looked at the pressure cooker and it doesn't have a guage on it. I managed to Google the brand name and found the manual. The manual recipe for stock says cook about 1/2 hour. Since I want the broth richer an hour sounds better. I was disappointed that the manual said to add only 2 pints of water to the bones. Its going to take forever to make enough to freeze for about a month. Cooking this way, could the bones be re-used? I paid about $10 for 3 smallish packages of neck bones and 1 package of knuckle bones.