Punching Bag On A Rail Most Secure Thing To Hang A Punching Bag On...?

Most secure thing to hang a punching bag on...? - punching bag on a rail

I bought a punching bag with a capacity of eighty pounds. I need an idea for something to hang.
I was thinking of steel rails, that my office door automatic garage (since I never opened my garage door), but I am afraid that doing the heavy weight of the bag somehow hurt ... What do you think?
Other ideas?

Much appreciated.