I had issues with my same gun set up too. Except mine fired everything I had ok, apart from Eley Match and SK Long Range. Eley club, standard and sport all went ok. I didn’t have light strikes but I had failure to extract, for about 30% of the match and long range. Never had a single failure to extract before chucking this Ibi barrel on. I emailed their support people and the response was to try headspace and then extractor spring, which you can’t get. My Ibi barrel tenon length is also about 2.5 thou (at least) shorter than the original barrel. I had already ordered barrel and bolt shims, anticipating a headspace issue.