FX is superb at keeping records, providing links on their website to diagrams and parts lists as well having parts available for their guns
There is also a wealth of quality info and repair videos on the net.
Search "Ernest Rowe" for starters
FWIW
Daystate, a laggard in this area , has begun a workshop series of videos/texts about disassembly/reassembly of a few of their guns.
The videos are very well produced and informative IMO
As mentioned by
@Treefrog The Crosman archives run deep
Access to their parts lists also makes it possible to order parts by model and part number by phoning the usually knowledgeable staff in upstate NY
Hope this helps
If the guns in question are Crosmans or Sheridans, you're in luck. There are pdf files out there that cover pretty much all of the older ones.
The Crosman web-site has manuals and exploded part diagrams that you can download for free.
Cheers,
J~
Some are Crosman, in which case they don't have quality pictures, diagrams, or information, which really surprised me. I would have thought Crosman would have great colored pictures of every gun they ever produced along with details. I will try some of the other sites Thanks. I'm amazed at some of the older guns that are built much better than most guns on the market today. Especially Crosman & old Gamo's don't know why they quit making quality metal guns. Got a Crosman V300 springer in today that shoots great for 60 years old.