https://www.myhanse.com/whats-this-for_topic11985.html" rel="nofollow - https://www.myhanse.com/whats-this-for_topic11985.html

 

If so, nobody seems to know for sure

https://www.hanseyachtsag.com/hanse/fileadmin/_processed_/b/1/csm_HANSE_Self-tacking_Jib_94953e5dbd.jpg" rel="nofollow - https://www.hanseyachtsag.com/hanse/fileadmin/_processed_/b/1/csm_HANSE_Self-tacking_Jib_94953e5dbd.jpg

From the picture where the padeye is right next to the guardrail -  I would say it is for a Barberhaul to control an optional spinnaker (Not for a gennaker) - but they are perhaps a bit too close to the bow. Could also be for securing an inflatable dinghy stored on deck.

But the picture in  https://www.myhanse.com/whats-this-for_topic11985.html" rel="nofollow - https://www.myhanse.com/whats-this-for_topic11985.html  is different. That looks like an option to lock the jib-wagon to one side avoiding violent movements of the car.

The old xx1 series Hanse had track-limiters / Pin-stops on the Jib-sheet track. With these it was possible to lock the track-wagon when reaching. 

 

Ah...that one. Yes, that's for a barber hauler. Makes quite a difference to the blade jib when reaching

 

Hmm. Not sure it's for that. The picture probably doesn't show it but its about half teh way inboard from the end of the track so wouldnt really work for locking the car. Maybe Jon is right and it's for a harness point. They started appearing on all Hanse's about a year ago (not fitted to my 418 and no deck reinforcement in that position shown in the deck plan either)

Do you have any recommendations on how to rig the barber hauler at the sail end?

This is how I set up a barber hauler system on my 341.  To the barber hauler control lines, I attach a snatch block (opening block) to the self tacking jib sheet when we are off the wind.

A full description of my setup can be found here, which also covers a simple method of goose-winging the jib.

https://www.myhanse.com/controlling-the-jib-downwind_topic10476_post88083.html?KW=jib#88083

Your system will obviously need to be a bit more robust, but the principle should hold the same.

For me, the prime objective of using a barber hauler is to control the twist of the jib, rather than widening the sheeting angle.  As you ease the jib sheet, the effective sheeting angle goes flatter in the vertical plain so the jib can twist more.  If you set the top of the jib correctly, then you are over-sheeting the bottom part of the jib, whilst conversely, if you set the bottom part right, then the top will flap or actually flog quite violently.

The picture shows my set up with my present jib that has battens in it, for the original jib from Hanse, I also used to tie a snap-shackle to the top of the block and clip that over the other part of the sheet as well to further tighten the leech.

If the apparent wind shifts by more than 10-15degs, then I will adjust the barber hauler to suit as well as adjusting the sheet.

Once the wind goes around 20degs aft of the beam, then the guard rails limit its effectiveness, in which case Matts idea of another sheet may be better.

Over the years, I have talked to a number of UK Sales personnel for Hanse saying that Hanse should offer a barber hauler system as a factory option, as I consider it a vital sail control.  They always talk to me about using a gennaker instead, but in my view as we sail 2 up in Scotland with shifty, gusty and occasionally strong winds, I say that idea is not a viable sole option.  So I concentrate hard on getting the best out of the jib.  Thankfully, it looks like you have a starting point for the system.  

could you make a picture from a side to show where on the toe rail the barberhauler's block is?