Hi
When I received my 8th Hussar cap badge upon completion of my TQ3 in 1985, we bent up our balls of the slider. This was to allow for the length of the slider pocket sewn into our issue berets to fit the slider on the badge. For some reason the badge slider was longer than the beret's pocket. As well, the bent ball would provide some resistance to the cap badge falling out.
These were QM issue badges and berets and we were rapidly encouraged by our leaders to acquire brass badges and "belgique" style berets ASAP.
Here is a nice early variety VIII CH badge. A bit beat up but lovely Coronet details. May be a Cartouche badge. "J.R.GAUNT" and "MADE IN ENGLAND"
regards
Darrell