There are a few answers for this:
Write Me Real Soon, Working Memory Rating Scale, Water and Mineral Resources Section, White Mountain Research Station.
In the case of firearms, it stands for Winchester Magnum Rimfire.
Only if that is what is marked on the barrel. 22 LR and 22 WMR are not interchangeable.
win. mag. rimfire
Yes
As in .22 WMR? That is the full name of the cartridge- the .22 Winchester Magnum Rimfire- usually called the .22 magnum
There is a .22 WRF, and a .22 WMR. WRF is Winchester Rimfire. Bigger than a ,22 Long Rifle, but shorter than a .22 WMR- Winchester Magnum Rimfire. If someone is using the term .22 MRF, it is an inaccurate term.
No
WMR stands for "Winchester Magnum Rimfire," referring to the .22 WMR cartridge, which is a rimfire cartridge designed for rifles and pistols. It is more powerful than the standard .22 Long Rifle, featuring a larger case and a heavier bullet, making it suitable for small game hunting and varmint control. The .22 WMR is known for its increased velocity and range compared to the .22 LR.
.22 Mag shell only.
Yes
Winchester Magnum Rimfire (WMR)
No. The case of a 22 WMR is longer than that of a 22 lr, so the cartridge won't fit in a rifle that is chambered for 22 lr.