They are for retaining the cams within the spindle nose. Certainly shouldn't be loose. Unless your system is unconventional or not original, I suspect there should be a spring and a pin behind them that mate with a groove in the cam. It may only be the spring force that is preventing them from coming completely undone.
On my Bantam (and in the spec) the bolt is a cheese headed thing that bottoms out hard against a counterbored shoulder, so I'm not convinced your grub screws(?) are original or correct.
Perhaps a Boxford owner could confirm.
Here's a link to the spec for the Camlock system **LINK** showing you how it works and the recommended components. See 33.5.2 and 3.5.3 for the bolt and pin. No spring is shown unless I've missed something.
Murray