Looking for ammo damage

Im trying to make my own Tranq shot for the longneck rifle and I got it all working, but Ive been looking where to reduce the damage and so far have not found anything if anyone can help me I will appreciate it thank you in advance.

I have found it, Is on the rifle Config area where you change the impact type, Also new question, I made duplicate of the rifles and reparent them to my new rifle when using the tranq ammo, but the attachment does not work can anyone help me when I drag and place the bullet it removes the attachments.