I would like to give you my opinion. I tune hatsan's and these are the most powerful spring piston airguns that you can buy. The problem with these Hatsan's are QC. Here is what you need to check right out of the box. First you have to take out the suppressor . That's 2 things that look like hair curlers and 2 plastic spacers. I would run at lease 5 pellets down the barrel first. Break the barrel open DON'T cock it, with a cleaning rod push the pellets through the barrel . You should feel a very small resistance all the way to the end. If not the barrel might be bad? Once you have established the barrel is good now we need to check the breeck seal. This is an easy test, simply get a kleenex and make sure you pull it apart so all you have is 1 ply. Tear it so it fits down in the area where the port hole meets the breech seal. Now when you are in a safe area to shoot cock the 135 , point it at your SAFE intended target put the pellet in the barrel ,close the 1 ply kleenex between the breech seal and port hole and shoot. KNOW YOUR TARGET AND BEYOND! All you should have once the gun has been shot is a single hole through the kleenex. I will also say this the bigger you go in caliber the more power you get and the recoil drops off. It has nothing to do with using a heavier pellet for me anyhow with my experience? I have this 135 in 22,25,30 and I have to say the 30 puts a hurt on what ever you shoot. I hate the cost! The 25 is a happy medium,nice power and shot cycle. The cost of pellets are more reasonable. I hope this helps? If you have any questions please shoot me an e-mail and we can talk in more detail.