FOC is usually pretty easy. If you just stick with broadheads that weigh at least 100 grains, your FOC will usually be okay. If you use feathers instead of vanes, it'll be even better. If you use 5" vanes or really thick,heavy vanes, you might need to bump up to 125's.

Completely ignore any broadhead that weighs less than 100 gns. Leave those to the Xgames type guys who love tippy-toeing around on the thin edge of sanity.