Do you use pink salt?
I don’t use pink salt for the brine, but I do use it for normal food prep. You use less salt for the brine when you use a fine ground salt, but I don’t recall what the correction is.
I also don’t use the nitrates that are in store-bought pickling spice, so my corned beef isn’t pink like when you buy it. The nitrates seem to give me headaches so I stay away from it.