I've used normal bolts not lock ones. Came loose once and it was because the head had started to unscrew not because of the bolt moving. Once the bolt is wedged in I've been able to bounce the pole upside down and it's not come out.
Also you don't need anywhere like a whole meter of threaded rod, only need a handful (should that be hand length?) more than your bolt length.
I've used normal bolts not lock ones. Came loose once and it was because the head had started to unscrew not because of the bolt moving. Once the bolt is wedged in I've been able to bounce the pole upside down and it's not come out.
Also you don't need anywhere like a whole meter of threaded rod, only need a handful (should that be hand length?) more than your bolt length.