That was my first thought too Cliff, but.... (pardon the pun)...
It was actually the other way around. My grate therms on lid is about 2" above main grate level, but for this smoke I put the butt on top shelf, and used my maverick placed about 2 inches from the meat for top grate temp reading. It ran 20* to 30* higher than the lower grate temps all the time.
Smoker heated up @ 385*400*, for two hours before temp dropped down to 335*. I brushed the grates off when it hit 400* for awhile
Butt went in at 335*, after an hour on counter ,while prepping and waiting on smoker.
Two hours maintained 300*-320* before having to add lit coals when it hit 270* briefly around the 2 1/4 hour mark.
Six hours maintained between 280* and 295*, with some spikes to 315*-320* Could not keep it above 280* without added small dry Maple branches for fire, but I soon ran out of those. Breeze had died to nothing, and I even took a fan out to blow on it, but that seemed to cool the smoker more than stoke the fire after dark.
Didn't want to burn any more fuel as I wasn't getting high temps anyway,
so finished in oven un-covered @ 340* for 1 1/2 hours. Over cooked it a bit. Didn't pull out until 207* IT.
IT was at 187* when I brought it in, and I think I should've just tented it then, to rest.
If my times in this post don't add up, it's because I miss-read my log.
My conclusions: If using CG, get some very dry small wood splits to use for heat. Learn how to maintain them, for heat.
And Butts, Briskets, and Salmon probably do best in a smaller vertical smoker. Easier to control the variables.
But, it wasn't a disaster!
Just took longer than planned. I think heat control was my problem, as well as well as a small chunk of meat in a large smoking chamber.
I had to force myself to remove and eat those shards of meat,
so you could see the smoke ring on it too.
There was no "Stall" as such. IT Temp rose steadily, each and every hour. It just did it too slow. As Tim Taylor used say... "Ungh... MORE HEAT!" LOL
Edited by fpmich - 7/10/15 at 2:18am