Quick update. So turns out there were a couple of bbs stuck inside the hop but it took a lot of fiddling to get them out as I’d already tried clearing the barrels. One of the bbs that came out was quite chewed up, so I don’t know what caused that! Then on the next fire test (only loaded 3 bbs in the mag) same thing happened, so pretty sure it’s a dud gun. Contacting Bullseye to get it resolved.