As a youngster about 10 or 12 yrs old or so, I remember going with an older brother into an apricot orchard and shooting crows and ground squirrels with birdshot using an old beat up .22 rifle. Can't say, as I've seen any rimfire birdshot since those days long ago. Is it still be produced by any of the ammo manufacturers? I have seen the stuff CCI makes for .38 and .44 special/magnum.