The Eley Z Long and the Eley Zimmer LR are not the same.
The Z long is louder than the Zimmer.
They may share the same velocity (800 F.p.s.) but their energy is 36 ft.lb. and 57 ft.lb., respectively, due to Zimmer's 40 grain projectile, as compared to "Z's" 29 grains.
I order the Zimmer by the case (5.000 rounds) via a gunshop. Delivery takes more than a month (I am in Western Europe), and once it took two months to arrive!
The Old Western Scrounger used to carry it in the States, but does not seem to list it nowdays.
It's a pity.
It is one of the best ammo around.
Sometimes I wonder if Eley Co. in Britain still produces it, since I keep getting "older" production/lot code #s.
The Eley Zimmer Lot #s I use are: ZLC005 (made in 1998) and ZLD007 (made in 1999).
Crete