I am new to air guns but always thought they would be fun. I bought the bottom line crosman fire. I have lots of guns so not new to shooting in general. After receiving the rifle I cleaned the barrel, switched out the scope for one off a 22 rifle I have, and purchased three types of pellets. In my initial shooting the gun shot at best a 3 inch group at 40 ft.. I made the assumption that as I shot it the accuracy would improve. I have now shot about 300 rounds through it. The more I shoot it the poorer he accuracy is. Now it is shooting a group of about 6 inches at 40 ft. I have checked the scope mounting, stock to frame screws, etc. and found all to be tight. The trigger pull is unchanged and in fact I am getting used to it and don't mind the creep so much anymore. With the current shot groups the gun is useless to me. I can't target shoot with it or hunt. Does anyone have any idea of what the problem is? I could have bought a better gun but even this cheap one should not be getting worse the more I shoot it. I enjoy the air gun and would like to have a accurate one but this is not it. Any advice would be appreciated.