A good stop for luncheonmeat when hair rigging for Barbel are the 'Fox Luncheonmeat stops' with a short bit of the tube that comes with them. the meat doesn't come off even when you make a big cast. see link-->
Fox Luncheonmeat stop
Although if your using small pieces on the pole then the
'Korum quick stop spikes' would be more suitable.
Heres a link showing you how to tie a hair rig using the
knotless knot.