Just recently I made my own experience with Jinhao pens and Bock nibs
(JoWos are somehow not available for end users in Germany!).
I got #5 replacement nibs from Gullor that are suppposed to fit in Jinhao 250/301/500/5099/8802/9009/5000 pens.
The #6 nibs were promised to fit in Jinhao 159/450/750.
So these Models should be interchangeable.
The Gullor nibs fitted well (respectively), but they are just as thin and hard nails as the Jinhaos.
I have four Jinhao 250; with two of them the nib section was loose and slid out when I inserted a cartridge.
What seemed to be a bug turned out to be a feature:
Instead of the Jinhao nib section I could insert a Bock
160 076 triple and it fit better in than the Jinhao one!
The cap of the 250 has enough room for the rather broad
160 076 Bock nib.
Encouraged by this I took a gun cleaning stick and pushed out the other 250 Jinhao nib sections as well.
They were glued with only little glue and cam out easily.
The gun cleaning stick has the advantage that its end is hollow so I did not damage the Jinhao feed at all.
Maybe all Jinhao 250 are like that or just my 4. (I tried the same with my x750 and it would not go).
Just be careful: The Jinhao cartridge feed is slightly broader than the standard Pelikan (Bock) feed.
Standard cartridges will fit into both, but anything that has been in a Jinhao feed
will be too wide to securely sit in a standard feed again. This is important for converters.
I also have a Jinhao 8802 where I could not push out the feed section (I didn't dare to push too hard),
but there I could fit a 180 Bock nib into the Jinhao feed. It was a bit tricky,
(maybe the Bock nib is a tickle thicker) but in the end it worked.
The 180 Bock nib is slimmer than the 160 which is too broad for the thin cap of the 8802.
A Bock 60 nib should fit as well; they are all #5.
I am waiting for a shipment of Jinhao 500, and eager to try my luck.
I had to edit the number of the Bock triple I put into the Jinhao 250: it was a Bock 076.
Edited by Brandywine, 17 November 2017 - 23:18.