I'm gonna grind some brisket trim to make burgers.
Are you using the whole packer ?
I trim them like I'm going to smoke it whole , then cut into strips . Grind one time through the 1/4" plate , then mix it into itself . I don't freeze the meat , but it's around 32 or 33 degrees when I start . Always under 40 when I finish .
It's loose , but no real issues doing regular grilled burgers .
Smash burgers I have to be more careful .
I usually combine my sausage making with my brisket grinding . So I have in the past added pork butt to the mix . I've also used a strip or 2 of bacon if the mix is lean . Grind the bacon if you're trying that . I chopped it once ,,, I didn't like that at all .
Sirloin is a great addition as well if you have it . I've used rib roast , strip loin , just depends on what I have on the counter .
I've also grated a yellow onion into the bulk grind before shaping the patties . It's mostly juice , but of you like onion flavor , that seems to add something to the binding .