How long to smoke lamb shoulder
Smoke lamb shoulder at 250°F for about 6 to 8 hours, and pull at 200°F, probe tender, for pulling. That is for lamb shoulder (bone-in, for pulling), at the heat shown; the calculator above has each heat a source gives a time for.
At the stall, wrap at about 165°F, in foil, if you like. Rest 20 to 60 minutes before slicing or pulling. USDA counts lamb shoulder safe at 145°F with a 3 minute rest; a thermometer in the thickest part tells you more than the clock.

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Questions
What temperature do you pull lamb shoulder at?
200°F, probe tender, for pulling. Cook to that temperature rather than to the clock.
When should I wrap lamb shoulder?
At the stall, about 165°F, in foil, if you like. Wrapping pushes the meat through the stall; left unwrapped, the meat builds more bark and takes longer.
How long should lamb shoulder rest?
20 to 60 minutes, loosely covered or wrapped, before slicing or pulling.
Should I cook to time or to temperature?
To temperature. The time tells you when to start and when to start checking; the meat is ready when the thickest part reaches its pull temperature.
Does my smoker change the time?
Not at the same temperature, as far as any cooker maker or test says. What changes is how steady it holds: keep the lid or door shut and the fire even, and the time holds too.
