@joshua.armour I’ve seen that the 2nd roast has better heat characteristics with every “drum” roaster I’ve owned including the gas-fired roaster that I built. My explanation for it was that passing through a complete initial roast gets everything in the roaster completely up to temp such that the 2nd roast reaches 1st/2nd C’s a bit faster. 2nd C in 13 minutes is very acceptable IMO, especially for a 1Kg qty in this roaster as you accomplished with the 2nd batch.
For near or max batches, I’d still like to have some head-room in heat for the Bullet for the times that I want to shave a few minutes off reaching 1st C. IMO, drum roasters are best when they have enough headroom for me to drive the roast a bit harder than the shortest user-desired period leading to 1st C. There’s always the balance between the designer’s vision or limitations and what the user wants to do and that is understandable. So, I’m speaking from a personal desire perspective as a roaster. That head-room ability is often where gas-fired roasters usually have the edge and electric roasters can bump against limitations.
Something I once saw in one of Tom Owen’s videos at Sweet Marias has stuck with me. In essence, Tom made the suggestion to try some non-std time-frames in reaching 1st C of 7-9 minutes vs the 9-12 that are often targeted. So, I began trying that with the 1.5lb batches in my gas-roaster and the results (for
me in the cup) were a nice surprise. But, you gotta have the power (heating) headroom to pull that off.
PS: Just for a bit of clarity, I’m not suggesting that a 7-9 minute 1st C is appropriate for all batch sizes or beans because it isn’t. It was the idea that Tom floated of getting outside my normal box of thinking for 1st C time-frames that I’m speaking toward. Related to the topic at hand (with large batches), I’d just like to have a bit more headroom in power for exploration, but am also very happy with my Bullet.