I am trying to locate brass for my new old rook rifle in 250 Rook. I have dies and RMC brass on order but would love 10-20 reformed or machined cases to get started now. Anyone have some to spare?

It can be re-formed (with rims thinned) from .22 Hornet.

50 grain cast .251 bullets for .25 ACP are said to work well.

Thanks Parabola. I’m without a lathe to do the rims properly. Will give that a shot kludging with the drill press if I don’t find a source

IF there is enough depth in the Hornet case web (you would need to section the brand you are using) you could face off the back of the case head until the breech closes and then use a small primer pocket unifier or flattened drill bit to deepen the pocket to fully seat primers.

This probably won't be much help as these aren't easier to find but both the .22 WCF and the 5.6x35R Vierling are very close to Hornet cases with .055" nominal thick rims. Maybe opens up your choices?

Edit: Buffalo is out of stock on the .22 WCF but maybe getting on a notification would yield results? Link => https://www.buffaloarms.com/22-wcf-winchester-center-fire-22wcf.html

I do need to look for 5.6x35r for a different rifle…a martini by Francotte I thought was in 22 Hornet but chambering Is really difficult. Pretty high grade rifle. Haven’t cast it yet

For my 5.6x35R BF, I make cases by thinning the rims of 22 Hornet cases. I just face the rear (bottom) of the cases, just barely removing the headstamp. This avoids confusion and sectioning the cases I used shows adequate web thickness is left. This would work as well for the 250, and others based on the same head size cases. A lathe is a requirement of life, a mini size lathe will work. If I can do it, anyone can.
Mike

Another board member is helping me out with rook brass so I am good for now regarding that need. Apparently I need to start researching small lathes.

I appreciate the information and help. Thanks.

Chris