Has anyone else had a problem with there Hatsan Blitz .30 losing power? When I got it, it was shooting 730fps then all of a sudden it dropped to 485fps. I have adjusted the hammer spring, cleaned all the moving parts, replaced the breach seal, and still can get it back up. I have called, texted, emailed Hatsan and I get no response. I have asked around of who works on these and I have found no one. Several people told me they were junk and wouldn't touch it. Any help would be appreciated