time and temp for large top round roast

[rayfrompa]

i am cooking large top round roasts for roast beef sandwiches. i have large roasts (15 and 13 lbs.) i’d like to cook them to medium, medium rare at 225 in my cooker. how long should i cook them for. i appreciate any advice or reference to some table or chart, etc... thanks ya’ll

 

[wbf610]

The only way to be sure you hit target temp is to use a thermometer.

When you say large, how thick? Are you putting the roast in cold, or letting them warm up a bit first?

 

[chilerelleno]

I do not recommend 225° for smoking beef roasts, ribs and the like.
I highly suggest you go 275° or higher for best results.
Time isn't a factor, internal temp is the Holy Grail here, you want an IT of 130° for a nice medium rare.

You must have either an accurate leave in meat thermometer or a hand held meat thermometer to check IT.
I suggest both, decent digital therms of both types are relatively inexpensive and widely available.
A decent entry level dual probe digital thermometer, one for cooking temp and the other for meat can be had for $30-$40.
A good handheld digital instant read probe can be had for $30.
These are absolute must haves in my opinion for top notch BBQ.

 

[SmokinVOLfan]

If you smoke at 225 I’d suggest a reverse sear. I’ve done beef tenderloin round roast whole ny strips etc... this same way with great results. IMO if you smoke lower temps you get more time in the smoke. 225 to around 120-125 pull it and roll it around on a hot grill to sear all sides. Should get you to 130ish then let it rest and cool. Pop it in the freezer for a couple hours then run it through the meat slicer. You won’t be sorry! Here’s some I did a few months ago with eye if round.