Well how lucky am I, last week I was given a Mk2 577/450 barrel in reasonable condition but with lots of light rust and some tacky mess like rancid waterpump grease mixed to a near solid mass, and today I tore the workshop apart to find enough bits to rebuild her. There is no pitting and the bore and chamber would rate 8/10. I tried one of my cast pills and rifling is full depth at the muzzle and as tight as!
First a nice buttstock with some fiddleback features, then a matching Mk3 forewood, the first complete breech block I found was striped and had a broken main spring. Fortunately I had a spare. The firing pin had already been bushed and protrusion measured at 0.037", perfect.
Will share some pics tomorrow as all the bits get cleaned for reassembly.
Trigger assembly, tumbler, lever barrel bands and all the bits are complete.
Am soaking the bits in diesel overnight to loosen the rust and tomorrow I will start sanding the timber.