I've had barrel cookers for what seems like forever. The old style, where we just cut a square panel out of the side, to load more briquets or lump,notched out the rim for the rebar, hung our chickens, tri tips, or whatever, and let it rip. An old steel for the fire basket, more then enough for a load of chicken or tri tips, I did lots or whole turkeys and prime rib, by adding more fuel as needed, and borrowing the lid off my
Weber kettle.
I also built a new style UDS. Nice features the old style did not have. Ability to regulate air, therefore temp. A grill for those things you don't want to hang. And, in my case, a bigger fuel basket. I wrapped a 1 ft wide piece of expanded metal, around a propane tank, tacked it together. Holds 20 lbs of fuel.
If you use the minion method, to start your fire, it will take a lot longer to get hot. Use a FULL chimney of fuel, leave the barrel lid off until its GLOWING, now, you have the higher temp.
For those of you who have never cooked hanging meat just over a glowing bed of coals, you might be surprised that it doesn't burn the meat. Not at all. Juices start flowing, drip onto the coals, and give it an unique flavor profile. I used nothing but briquettes for probably 30 years, then started mixing in smoke wood with the briquettes. I started using Lump when I built the UDS, and really like how it cooks and tastes. I noticed a taste when I used Kingsford the last few years, that I hadn't noticed before. The lump fixed that.
If you can bend at the waist, you can do away with the gate valves and just use magnets to open or close the holes. Works great, they don't get hot at the bottom of the barrel.
Another mod I made. I drilled 10 holes in the rim of the barrel, to act as my exhaust, and, to allow me to hang halved chickens or Tri tips when a crowd is in the works.
If you can drill a hole, you can build a barrel. After building the new UDS, i liked the expanded metal basket so much, I wrapped a piece of it around the steel rim of my old barrel. No more having to add fuel when cooking a big turkey. I still use them both, here I was cooking chicken for our fishing clubs get together.