I have been working for 1-2 years on my No.4 project. Nice bore and worth the effort, But things are at stalemate and I have no ideas. I have installed the extractor and spring on my bolthead and now the bolt will not close, as best as I can see the extractor is striking the rear of the barrel. If I remove the extractor the bolt will full close. The extractor came out of an unopened box ofNo.4 surplus parts out of the UK. Not sure what is/isn't going on. Do I have a No.1 extractor? No idea here. Thanks you, guys.