Great explanation from Johnny, most of use don't take an internal temp on ribs. The 3-2-1 is preety much spot on. It's all good my friend.It is almost impossible to get an accurate temp on ribs.... not enough meat and to much bone for that. If you what Rob said 3-2-1 or 2-2-1 you should be golden, or if you prefer not to foil you ribs keep your smoker temps lower (210°-220°) and after 5 hrs. do the bend test. The bend test is where you use a pair of tongs to pick up a rack of ribs about 1/4 - 1/3 of the way from the wider end, if the rest of the rack bends straight down 90° and you start to see the muscle fibers start to pull apart, then the ribs are done.
The bend test generally does not work well if you foil your ribs because they can get fall apart tender when you foil them, so when you go to pick them up they break in half.
I wish I could take credit for that one Bear.... I got it from watching a Food Network special on BBQ joints. Some old guy in KC who had been working at this smoke house since he was a kid showed how it should look an camera... lol. Figured he must know what he was doing since he had been doing it for 50 yrs. and was still in business... lol.
Yup... bend test works with any full rack of ribs. If you have cut the racks in half it wont work as well, but as long as they are full racks you should be fine. For baby backs you might want to check them after about 4 1/2 hrs. then decide if they need another hour or so. The other main trick is keep the temps low, around 210-220°, if you cook them to hot they will tighten up and lose a lot of moisture.
