Rogelio; was shooting .22 Colibre's. They specifically (Aguila) specifically state that you are not supposed to use them in rifles. They are only powered by the rimfire primer, Aguila recognizes that they may not have enough poop to make it out of a rifle barrel. I use them in a rifle all the time too, However. I just make sure they come out, and don't mix e'm up with other LR ammo. Sorry Rogelio