Cody the trick here is to put a LIGHT tension on the blade and to let the blade do the cutting. I know, I know what else does the cutting? Seriously though with those light blades it takes a slow to medium speed, a lighter tension on the blade than normal and a very light touch when cutting it. Practice will make you find your sweet spot on speed, pressure and tension for cutting brass. One other thing will be that the metal will wear the heck out of your blades, especially on a faster speed. Here is one example of what I am talking about. I did this about 3 -4 years back and like you broke a ton of blades until I learned how to cut it successfully.
DW