Gents,

I'm planning to open up the HW80T I picked up last week to try and work with a bit more depth what if anything has been done to it, this will effect what I do next as regards a restoration.

As noted before - Stock has been confirmed as 80's venom, miss match bluing action to barrel and up to a 30 year life could mean anything has been done to the action over the years and its almost evil to cock and previous owner admitted to re-springing it recently.

What am I looking for externally and then internally, in the way of clues and markers and non standard parts and machining as I play Sherlock Holmes.
E.g. I recall on 77's pistons were typically blued on Venoms upper end of tunes, and you could look for button drag marks in the grease.
Any similar tricks to ID'ing an 80 ?

Much as an enthusiastic teenager in the 1980s I opened up any air rifle I could lay my hands on, I've only done it once in the past couple of years, and may need a picture or video guide on this too.

Thanks in advance
Harry