A couple of questions (1) was this a one time thing or has it happened a few times ? (2) Are you sure that your temp gauge is correct or do you have multiple gauges ? I don't have an insulated cooker but it seems like 225 degrees would cook at the same rate in an oven , uds, RF or what ever you're using. I'm just curious, what did the manufacture have to say about this ? This jm2cw and I'm sure some other guys will be along to give you their opinion as well.
The ambient temp of the CC may not be taking in consideration the radiant heat from the BP. I would recommend taking a large foil pan put 1" of water in it place a rib rack in the pan, place your brisket on that. This will create a buffer from the radiant heat and allow a longer cook at the same CC temp.
Jm2cw
Current Smokers: Backyard RF Offset and Hybrid RF Offset trailer rig with Cowboy cooker and fish fryer, always room for more........
This fast cooking thing has happened every time I have cooked on it. It's the same with briskets, butts, sausage or ribs. The smoker has water pans under the meat racks. I don't use them because I don't want the steam. I am going for the crispy bark. We live in Texas and that's the Central Texas type of BBQ. I do have multiple temp gauges and they are within 5 degrees of each other from one end of the pit to the other. The pit is really well tuned.I have also used the Maverick to confirm that my thermometers are calibrated. We have also used boiling water and ice water to check the accuracy of the therometers.
The manufacture is mum on the issue. There are other issues with the build and they have not been addressed either but the meat cooking too fast is a priority at this point, we will address the other issues later after we get good tender, crispy barked, juicy, fall apart brisket and pork butt coming off of the pit. The pit is 8 feet long by the way. We have never cooked a full load (three shelves) because we can't get a small load of meat to come out right. A full load of meat would be $700 - $1000 so we are just ready to gamble yet.
I cook brisket at above 300 degrees as many do.... never check an internal temp.... when it probes like butter I pull it.... many people are cooking hot and fast with great success..... just my opinion!!!!!
Myron Mixon claims to do it that way all the time…
And on the eighth day God created barbecue …. because he DOES love us and he wants us to be happy.
Current smokers: Egor (trailered RF) and Easybake (tabletop pellet drive)
Just weighing in but have you tried a cook at the various levels? I can see if it was a single rack set up and the rack was too close to the plate but it sounds like this is a fairly large rig. Have you hooked up a digital therm to verify your manual gauges? Only other thing I can imagin is too low of an air flow which will get you BP pretty darn hot since the air is sluggishly moving through the rig. That just goes back to the multi level experiment to see if the top rack cooks slower than the bottom rack. Well there's m2cw hope there is some help burried somewhere for ya.
If it can't be smoked .... try frying it. It that don't work, it's probably best just left alone
The sand is a great idea. I have'nt tried the different levels that will have to be one of the next attempts.
I probably need to go ahead and spring for a full load of meat It's not easy to pull the trigger on $700-$1000 worth of meat.
That is a small investment when you consider that you already have several thousand dollars invested in the pit.
If you're putting on that much meat then the meat becomes the heat sync ….. You might just be looking at the low-load results for that pit and a full-load may end up back where you want to be.
And on the eighth day God created barbecue …. because he DOES love us and he wants us to be happy.
Current smokers: Egor (trailered RF) and Easybake (tabletop pellet drive)