Digging for info - front drum explosion on 727s

Most of all the big explosions that I saw were in the 1960s
when converters .were not very advanced and traction was
limited = Often racers would neutral start their race cars with
sometimes disastrous results.
I have broken the sprag a number of times with both style valve bodies
and never hurt the drum (Even the light Aluminum Drums). Maybe I was
lucky for a change.