[r-t] Extent of Double Grandsire Doubles

[Francis Herne]

On Friday, 28 June 2019 22:16:29 BST James Ramsbottom wrote:
> Hello All
> 
> Is it possible to get a single extent (i.e. 120 true changes) of Double
> Grandsire Doubles using only standard Grandsire calls? If not, is there a
> 120 which almost meets the criteria e.g. has only 2 special lead-end calls?
> (Someone asked on a Facebook group and I'm now interested to know myself.)
> 
> James

You can't get a true 120 with only normal Grandsire calls.

(there are some 480s like https://complib.org/composition/24570 )

http://methods.org.uk/other/double5.htm has a 120 for Double Grandsire; it 
uses a normal Grandsire bobs but a special single (the hunt bell and 4ths-
place bell swap just before the half-lead).

Now to talk someone into ringing it...

 - Francis