On my low end I am getting about 1060-1100 fps bumped it up a bit and was getting mid 1300's with no sign of over pressure. One bullet I shot into I'd say an 11"-13" thick log went straight through and kept on truckin with almost no deformation, but this bullet did have some babbitt in the mix. I only had five 2 litre bottles filled with water to shoot at and those just vanished after one shot with the bullet getting lost in the dirt backstop.