All-time favorite is my Dad's old Winchester 74 .22 auto which he taught me to shoot with starting about age 5.  It now has a Leupold Alaskan (yes, Leupold) 6X set parallax-free at 50 yards and shoots 0.4" average 5-shot groups at 50 yards with good lots of Eley.  He bought it in 1941, and it has a barrel date of 1939.  

Pure iron-sighted plinking fun favorite -- Winchester 63.

Scope sighted plinker/squirrel smacker is a Shilen ss-barrelled 10/22 with polished action to feed standard velocity ammo and a KID 2-stage match trigger set up with 10 ounce first stage and 6 ounce second stage. Stock is a Ruger Deluxe walnut checkered factory stock with the barrel channel opened up for the heavy barrel. It shoots in the 0.3's @ 50 yards average with both Tenex and a good lot of Eley Standard. Very smooth shooting and accurate.

Also love my Compass Lake Engineering spacegun upper in .22LR with 24" Douglas SS match barrel (installed by Derrick Martin using a USAF surplus .22LR conversion unit, but has a true .22LR match chamber.)  It shoots 10-round groups of Tenex into 0.3" at 50 yards all day long, and is a blast to shoot.  Someday I'm gonna take that thing squirrel hunting!! [:)]
John