I’m not sure what you’re doing start at 500 then what?
You need to decide what result you want & find a recipe. You cant wing it.
I have a recipe. But the recipe is for an 8lb prime rib. I'm just trying to ask if I can still use this method for a 13lb prime rib.
Time is not the factor. It's the internal temperature you seek for your desired result. You can't do that without a meat thermometer. Look at a doneness chart & determine your desired result. Then, use a meat thermometer.
Salt liberally and pepper. Fat side down.. 5 min per pound at 500 degrees (this sears roast. Turn oven OFF
Do NOT open oven... 2 hrs.. sitting in oven... take out.. let rest 20-30 min then carve.. medium rare results
Have followed this recipe oven 8 times.. same results