these were tested in my stoeger A30 under 500 fps air rifle and i also tested them in my crosman phoenix as well and in both guns the pellets will not leaev the barrel they are cool and look great and all but these will not fire out of non pal or under 500 fps springer or nitro airirifles i did get them to fire out of my crosman 1377 pistol the speed was about 290 fps which i did expect and they did fire so these are made more for the .177 cal 700+ FPS Air RIfles for sure but defentally not for under 500 fps airguns at all .. other wise they are geat and you get alot of rounds for the money to also great and they are very well made.. so my opnion is unless your going to use them in a air gun that is 700 fps or higher then i would no even bother with them ..