Howdy Dan. First off, hope you had a great Thanksgiving. Lets see here. When you say brine, do you mean marinate? Smoking jerky is kinda tricky because its hard to get allot of smokers to the low temps that it requires. Around 100 degrees. At 180, you are really accelerating the processes and more or less cooking it. Are you using any cure in your recipe?
Give this a try next time. Make sure your meat is cut to a uniform size, lets go with 1/4"- 3/8" thick by 1" wide cut with the grain.
Here is a basic Teriyaki recipe for making 3# of jerky.
1 tsp kosher salt, not table salt.
1 tsp insta cure or pink curing salt.
1 tsp ground ginger
1 TBL Brown sugar
1/2 ground black pepper
1/4 tsp cayenne pepper
1 garlic clove chopped up fine
1/4 cup pineapple juice
1/4 cup soy suace
Let this mixture sit in the fridge for 24 hours, removing a few times to mix things up.
If you want to make more just double or triple the recipe. Cure is used as jerky is made at a low temp and prevents the growth of nasty stuff.
Like DamMcG said, when you can bend it in a U shape without breaking, but close to it, its done.
