Any help is greatly appreciated. Ive been attempting to locate the Federal BOR Lock MZ 350 grain .50 cal. bullets for black powder season. I have successfully used Barnes MZ Expanders for years and believe they are the best bullet out there. My question is this, has anyone successfully used the Federal BOR Lock bullets and how do they compare to Barnes MZ Expanders? Also, if your a Federal BOR LOCK fan, where can you find them to purchase?