Does anyone know what would cause damage to the carbon brush within the dist. cap? Mine looks like it scorched. Replaced and slightly scorched looking again. What causes this....a dodgy coil perhaps?
Also while on the subject I'm keen to know how many you out there are still using the original copper plug leads? Are they better than modern ones. I'm using Magnacore (swear by them) but am I better off using original or copper leads??
Thanks awfully.....

did you replace the rota arm at the same time?

Check coil wired the correct way round. + to switch - to points (assuming negative earth).
Get this wrong makes the spark jump the other direction. (also makes it harder to start)
If the hole the brush sits in in cap is worn will make pin rattle around too.