They work perfectly, just as advertised.

Screwed down onto the tope of a tube of NL1000, a conical is slid in from the left into the lubing 'station' above the tube...your idea of a straight tube MAY work, but this aren'tstraight through tubes...they have a little design inside the tube that I'll call the "lubing station".

The lubing 'station' seems to be made up ofsome raised injection molded plastic ridgeslocated just so, whichI conclude keep the lube flowing up and around both sides of the conical, and not allowing it to just squirt left and right out each end of the cross tube...you can see the lube flow all up and around the conical.

When it's wrapped with lube,you slide in another conical, it forcesthe finished lubed conical forward out of the lubing station,and the new conical takes it's place.
Lube that one;
Insert another one;
Repeat;
etc.

When you push in the third one, the first one will drop out...Ilay a sheet of waxed paper down so they'llhave a place to fall without getting mess all over the table.....push a kleenex through after you're done and it's all clean.

I shot 2-3dozen.45cal Maxi-Hunters in one range trip after lubing them myself, accuracy was excellent, and there wasn't a bit ofleading.

Note:
If you're only going to do a few, you could probably do them by hand just as well