You've inspired me to rework my setup. By the way, I recommend you pull that saw apart and add some loc-tite to the set screws that hold the gears to the driveshafts....
I just used a dado blade, made quick work of it. However, just after the final pass on the table saw I thought I should have used a router and and left wood for the brass stop instead of glueing in a dowel. I may flip over the wood and do just that.
Do you use your finger to lift the brass out of the groove ? The reason I ask is if the stop was removable once cut the uncut brass could push the cut brass out of the slot ?
Brass sticks up high enough you just roll it out with your finger. I drilled a hole below so shavings could just fall through. Although most of them seem to go elsewhere.
On my set up you don't touch the brass once its cut. You simply add another case and they feed along the groove and there is a small hole at the end of the groove for the case neck to fall through and the case to go on over and out into a tray. I cut the groove with a table saw and put a roll pin in the wood for my gauge stop. I would bother to router unless you really want to.