ADB-BUTINACA are potent synthetic cannabinoid, much stronger than THC. Using a ratio of 0.4g per 30g herb results in approximately 13.3mg ADB-BUTINACA per gram of herb. This is an extremely high dose, especially for someone with no tolerance, and could cause severe effects, including dangerous side effects.
For a no-tolerance individual lower the dosage significantly. There are a lot of variables here, but I would put a starting point at the 0.5-2 mg of ADB-BUTINACA per gram of herb. Perhaps chemists will correct me. Gradually increase only if necessary, but always be aware that effects can escalate unpredictably.