Some use the meat pulled back from the bone by a 1/2" as an indication but we grab the bottom of the rack with a set of thongs and try to stand the rack up. If they bend in a V shape without breaking away from the bone they are done.
(Brewmaster and Pitmaster)
BBQ Team: Lawn Guyland Smokers
Brewery: Black Dog Brewery
"Sam I Am": XL Big Green Egg
"R2 and D2": Twin 22" Weber Smokey Mountains
Custom Made Automated Souped Up Sabco