Stick with the 150 grain BT' s. There is absolutly no reason to use a 180 grain bullet on deer size animals. From 50 yards to 500 yards the 150 grain ballistic tip will kill any deer out there. Deer are not big animals and do not require the penetration that a 180 grain bullet would provide. As it is, you will probably never recover any of the 150 BT' s shooting at deer.