Found this on a website after googling it. Someone is selling one loaded case on the site....
It is believed to have been developed in 1937 by Harvey Donaldson from New York. It derived its name from the fact that the second chambering reamer (made by M.S. Risley, Earlville, NY) appeared to be correct in providing what the designer was striving to produce. It is actually an improved or blown out version of the original 22 Lovell or 22-3000 developed by Harvey Lovell about 1934. Both are based on the obsolete 25-20 single shot case necked down, itself a wildcat when it first appeared in 1882. The R-2 was so popular that the late J. Bushnell Smith of Middlebury, Vermont and Griffen & Howe of New York City custom loaded ammunition in large quantities; when the supply of 25-20 single shot cases was exhausted, Griffen & Howe arranged for the manufacture of R-2 cases. These are specimens of those cases. I consider the 22-3000 G&H head stamp not only a wildcat cartridge, but a proprietary cartridge, as they were created by a manufacturer of the day, not homemade from another cartridge, as a true wildcat.
thejanitor