20lb 7-bone prime rib for New Years Day…how long for cook?

[RBBQ]

7-bone standing rib roast/prime rib. This meat monolith is 20lbs and will be going on the Flagship 1100 tomorrow for New Years dinner.
I’ve never cooked something so big, and have seen cook times/temp vary widely. Would like to do at 225/250 but most places I’ve seen are recommending 30 minutes per pound. For this 20lb this would be something like a 10 hour cook. Does that seem right, or have any other suggestions for a no-fail cook?
Thanks!
RB

 

[Threadcutter]

250 degrees setting on the grill.

I'd pull it at 117 degrees internal temp, sear the exterior on a gasser or stick burner (if you have one), then (re)wrap it in foil and a towel and put it in an empty cooler for about an hour. Longer won't hurt anything.

I've had them self cook after removal from the grill by as much as an additional 15 degrees, which I thought was quite odd. I've seen convential wisdom say an additional 5 degrees isn't unusual.

My internal temp targets are always on the low side. You can always put it back on the grill for a little longer, but once cooked, you can't "un-cook" an overcooked piece of meat. 117 degrees target has always worked well for me.

 

[RBBQ]

Thanks…any idea how long it might take?

 

[Threadcutter]

Thanks…any idea how long it might take?

I don't. I'd use the 30 minutes per pound rule of thumb and go from there. If it hits 117 internal temperature "too soon", it won't hurt anything to have it rest longer (wrapped) in the cooler.

The "predictive" thermometers (Meater + and Combustion Inc.) are handy in that regard. I have Meater +'s and will probably stay with them. The only downside to them in use is that they take time for the cook time to start calculating. It is because the probe is sitting in a chunk of cold meat and the Meater + needs to see temperature change/rate of change before it can start calculating time.

It's not a big deal because while it's "not registering", you can be sure that the meat's internal temperature hasn't begun to increase. In other words, just ignore it until it starts to register/calculate/predict.

 

[Beach Bum]

Thanks…any idea how long it might take?

I have done lots of 4 bone roasts but been a while since I've done full 7. Would you consider cutting to 4 and 3 bone sections? That would make the time a bit shorter and double the highly desired end piece count.

 

[Pacman]

Excellent recommendation @Beach Bum

 

[RBBQ]

Thought about cutting it in half…also thought about just removing bones and cooking them separately like a rack of ribs. I just trimmed it..took off more than I had originally thought…. hit it with some Ben’s Hefner Dust and stuck it back in the fridge for tomorrow. I’m gonna wing it and just plan for 6 hours. If it gets done early I can rest it in a cooler, if it takes longer, hopefully wont be that much longer and can crank up a bit on the heat if needed along the way. Wish me luck!

 

[RHEINLEIN]

Ate you tying the bones back onto the roast with twine?

 

[SmokeZilla]

You can cut the bones about 3/4 of the way to avoid their removal. Then season the area under the bones and tie the bones back on. During the tie job, try to make the roast in a manner that keeps it uniform in thickness, if possible. That will help minimize internal meat “doneness” variations. Be careful however that you take any possible “carry over” into consideration as the meat may rise another 5-7F following removal from the heat source. As such, it will be hard to predict how long the cook will take due to differences in beef grades, marbling, dry vs. wet brine or seasoning, inject or not injected, and other factors. Let your calibrated temperature probe be your guide and select the wellness minus rise time to get to your your perfect temp. I usually think of RRs more like an extra thick steak than a brisket or similar protein. For my cooks they rarely go over 4 hours unless I go below 245F (grill temp). The rest will take another 30 minutes as a minimum. As a tip for the bones, following removal from the heat source, remove them completely and sear the RR on all sides. Then, wrap the bones and put them back on the grill as they may take another 2-4 hours to render completely. That makes for a great after meal snack that is rich in beefiness. YMMV, good luck.

 

[Threadcutter]

You can cut the bones about 3/4 of the way to avoid their removal. Then season the area under the bones and tie the bones back on. During the tie job, try to make the roast in a manner that keeps it uniform in thickness, if possible. That will help minimize internal meat “doneness” variations. Be careful however that you take any possible “carry over” into consideration as the meat may rise another 5-7F following removal from the heat source. As such, it will be hard to predict how long the cook will take due to differences in beef grades, marbling, dry vs. wet brine or seasoning, inject or not injected, and other factors. Let your calibrated temperature probe be your guide and select the wellness minus rise time to get to your your perfect temp. I usually think of RRs more like an extra thick steak than a brisket or similar protein. For my cooks they rarely go over 4 hours unless I go below 245F (grill temp). The rest will take another 30 minutes as a minimum. As a tip for the bones, following removal from the heat source, remove them completely and sear the RR on all sides. Then, wrap the bones and put them back on the grill as they may take another 2-4 hours to render completely. That makes for a great after meal snack that is rich in beefiness. YMMV, good luck.

Nummers..........

 

[Threadcutter]

Thought about cutting it in half…also thought about just removing bones and cooking them separately like a rack of ribs. I just trimmed it..took off more than I had originally thought…. hit it with some Ben’s Hefner Dust and stuck it back in the fridge for tomorrow. I’m gonna wing it and just plan for 6 hours. If it gets done early I can rest it in a cooler, if it takes longer, hopefully wont be that much longer and can crank up a bit on the heat if needed along the way. Wish me luck!

 

[RBBQ]

I was fortunate..the butcher did cut the bones most of the way off. I folded them back, seasoned and tied it back up.
Wrapping the bones is a good idea…I think I’ll do that.
I bought a su-vide grill gun and will probably finish of searing it with that. Will report back on how it went along with the time. Thanks!`

 

[Waterboy]

@RBBQ here is a video from Hey Grill Hey where she addresses the timing of a prime rib cook. After about 10 lbs you get longer but not really bigger so not much difference in cook time between a 4 bone 10 pounder and a full seven bone prime rib according to Suzie.

 

[Beach Bum]

I was fortunate..the butcher did cut the bones most of the way off. I folded them back, seasoned and tied it back up.
Wrapping the bones is a good idea…I think I’ll do that.
I bought a su-vide grill gun and will probably finish of searing it with that. Will report back on how it went along with the time. Thanks!`

I was able to try that gun at my cousin's place. Enjoy!

 

[RBBQ]

@RBBQ here is a video from Hey Grill Hey where she addresses the timing of a prime rib cook. After about 10 lbs you get longer but not really bigger so not much difference in cook time between a 4 bone 10 pounder and a full seven bone prime rib according to Suzie.

Thanks! That was a helpful video

 

[RBBQ]

After action report on New Years Day cook:
After trim, 19lb standing rib roast. Hit with Bens Heffer Dust 24 hours before cook, and then slathered with herb butter mixture before putting on Flagship 1100.

Cooked at 225 for 4 hours.
Raised temp to 275 and cooked for an additional hour (5 hours total cook time)
Pulled at 120 internal temp and rested for 30 minutes. Decided not to reverse sear.
It was a bit rare for me and I ate from the ends, but these animals I cooked for wanted it rare. Generally you can plan for a 6 hour cook and if it gets done you can rest it in a cooler.

 

[Jim6820]

Oh, yeahhhhhh! That is perfectly done for me; I like a true rare.

 

[SmokeZilla]

I like the way you work. My favorite temperature, red and juicy. Congrats.

 

[Threadcutter]

After action report on New Years Day cook:
After trim, 19lb standing rib roast. Hit with Bens Heffer Dust 24 hours before cook, and then slathered with herb butter mixture before putting on Flagship 1100.

Cooked at 225 for 4 hours.
Raised temp to 275 and cooked for an additional hour (5 hours total cook time)
Pulled at 120 internal temp and rested for 30 minutes. Decided not to reverse sear.
It was a bit rare for me and I ate from the ends, but these animals I cooked for wanted it rare. Generally you can plan for a 6 hour cook and if it gets done you can rest it in a cooler.



View attachment 20980View attachment 20981

When you pulled it (at 120 F), did you wrap/cover/tent it ? And, did you continue to monitor internal temp after you pulled it ?

I'm curious if there was any additional self cooking that took place and if so, how much ?

 

[TheRicker]

I have done lots of 4 bone roasts but been a while since I've done full 7. Would you consider cutting to 4 and 3 bone sections? That would make the time a bit shorter and double the highly desired end piece count.

…and do one more or less done than the other to please those who like it more or less done.