Rear brakes were bouncing the rear end when I was stopping, and figured the drums were worn out, so I bought some new drums from Pepboys and the hub holes were about 1/8" too small in diameter. I figured the drums, like the rims were lug-centric, so I just die-grinded out the center hole.
Well, the rear is still bouncing, and I wonder if its the drums still after having them cut, or if its the shoes, or something else??

thanks

The brake drum is hubcentric. By grinding out the center hole you've most likely got the drum off center.

Great. Theres 75$ down the tubes... Anyone think Pepboys will take them back now?

Why did you grind them out in the first place? When they did not fit, I would have taken them back. Most every set of brakes I have worked on, on semi-floater axles have been hub-centric which is made real obvious by how tight they fit on the axle and the lug holes are always a bit bigger then the stud.

Take them back, why should they? On the other hand, are you not going to tell them that they gave you the wrong ones in the first place so you modified to make them work? Now you want your money back for a drum that you made into junk. In my opinion, you are going to eat the cost because of a mistake you made. If you take them back and do not tell them you modified them to make them work, that is being very dishonest. Remember, what goes around comes around so eat it and learn from your own mistakes.

the wrong part is the wrong part, id just bring them to a metal recycler so at least you can get a six pack for it

Do your wheels have one of these cheesy hub-covers in the middle? If you take it out, the hole is maybe 1/8" bigger. My guess is that the drum you got is intended for a wheel w/o that thing. Just a guess.