- I received this and have it all put together, but I have an issue when inserting the pin through the body and hop up when putting it back together. It is a very tight fit, and I have to use a lot of pressure on one side of the pin to get it to line up properly. Once it is align, the bolt won't cycle without using an incredible amount of force. It causes the hop up chamber to sit up just a bit too high, so the nozzle catches on the lower side of the bore when going through. Is there something I can do to fix this?