I have a wide collection of calibers ranging from .22-50BMG. While I am old school and my favorite is probably one of my .308's, but the ones that get the most action are my .22's. From .22 match pistols, to my CMMG AR .22 these definitely earn their keep. I teach people to shoot and basic fundamentals on these. I always tell people that a good .22 is one of the best investments as far as keeping proficient and even protection if needed. Ammo is cheap and plentiful.
" The strongest reason for the people to retain the right to
keep and bear arms is, as a last resort, to protect
themselves against tyranny in Government...." - Thomas Jefferson