One of the more obscure
.22 rimfire cartridges the .22
Winchester Rim Fire is still in production but only in very limited quantities, mainly for use with the antique
Winchester 1890. It is dimensionally very similar to the
.22 Magnum but is less powerful, pushing the bullet at only about 1400
feet per second, compared to the .22 magnum velocities of over 2000
fps.
The .22 Magnum and .22 WRF are not interchangeable. The .22 Magnum is aka the .22 Winchester Magnum Rimfire.