I get a kick out of some of these "You-tube" tinkerers and how they come up with some of their inventions. One major "gimmick" involves using an automobile oil filter for a silencer. Of course, not all oil filters now require a tax stamp, but the threaded device used to attach the oil filter onto the threaded muzzle now requires the $200.00 tax stamp. When we used to sneak onto golf courses as a kid because they were "over-stocked" with squirrels in their surrounding timber, we stretched baby bottle nipples over the muzzle of our .22 rifles to quiet 'em down a bit. Worked for around three shots, and that was it.