Over the past 40 years I've shot Winchester/Olin 22 WRF, Remington 22 Rem Special, and CCI's 22 WRF ammo in a variety of 22 Magnum rifles and revolvers without any trouble. I think that CCI's caution against firing 22 WRF ammo in firearms chambered for the 22 MRF has more to do with "due diligence" related to defending against any potential product liability litigation than any real or imagined problems.
They may be correct about firing their jacketed 22 WRF ammo in 22 WRF revolvers, since I suspect that there haven't been any new firearms chambered for the 22 WRF since before the US became involved in WW2.
Jeff
