I used to use YJ' s, then I switched to whatever was cheapest when I went to buy a brick, then I got smart, nothing goes through my guns except CCI Mini-mags. I quit using YJ' s because they' re dirtier than a $2" horse" and out of every tubefull, I' d have to jack out about every third round because it would misfire, very typical of remington rimfire ammunition. With the bargain basement stuff, it' s pretty inaccurate, and a lot of misfires occur, not to mention that I' d find the slugs pressed against the skull between the eyes, mushroomed huge, with it' s four counter parts sitting beside it, maybe one would get lucky and penetrate. Took about a week to give up on that idea. Since I switched to CCI Mini' s, I' ve never found a bullet mushroomed like that, everyone has penetrated well, if not exited, even on body shots.