So how are the new HW star nut barrels actually held in?

[Shed tuner]

Ah OK, thanks for that Jon, I take it that would be the same process for other companies blocks?

A sharp drill bit works on mild steel from all known airgun manufacturers

[look no hands]

A sharp drill bit works on mild steel from all known airgun manufacturers

I've heard Weihrauch use old Panza tank metal, so was concerned about the high quality steel Webley used to use

Pete

[harvey_s]

I thought they were splined, pressed and topped off with the star nut...Nice easy job then

[HW777]

I've heard Weihrauch use old Panza tank metal, so was concerned about the high quality steel Webley used to use

Pete

It was reputed that Weihrauch used WW2 ordnance to make their rifles.

Webley used Sheffield steel.

The metal now used to make rifles is below par of that from yesteryear

[Shed tuner]

I thought they were splined, pressed and topped off with the star nut...Nice easy job then

that's my suspicion too...

[landymick]

It was mentioned a good few years ago . Remove the nut , you might have to make something up to fit . Then press it out off its splines .

A straight push not screwed .

[evert]

It was reputed that Weihrauch used WW2 ordnance to make their rifles.

Webley used Sheffield steel.

The metal now used to make rifles is below par of that from yesteryear

Lothar Walther, Norica and some chinese barrels have been the toughest ones to machine of the ones I've repurposed.
Modern BSA barrels machine really easy, Gamos have been quite nice too if I remember correctly, and some chinese have been okay.
Webley barrels, no those would be sacrilege to start altering.