Phoenix Arms HP22 is mostly zinc
but it's been reliable and accurate for me. I have fired several hundred rds thru each of several Jennings J22's, and they worked ok. I seriously doubt that many owners of .32's, or 25's have fired that many rds thru their guns, despite owning them for many years. :-) American Handgunner Publisher/editor was proud of having put 1000 rds thru his seecamp 32 in a 10 year period! :-) I've put 1000 rds thru a M21 Beretta 22lr in one day.