I thought it was a joke! I just got it back from MVS to get it replaced, the first one was having trouble firing. This second bolt won't fire at all. I have tried everything! Tested it and there is no connection. I don't want to try to take it apart. I guess just having to send it back again! It's not MVS fault , they are awesome with how fast they responded and sent me a first replacement , sent them another email, please make it right guys. This is embarrassing to have It happen again. Lol!