Mike, here's the manual from the extremely useful Vintagairgunsgallery brought to us by Danny Garvin:
https://forum.vintageairgunsgallery....istols-manual/

This shows the valve version with a flat seal against a flat seat. Later guns use a ball seating against the seal, but the overall construction is similar and you won't know which you have until it's disassembled.

Here's a discussion that may be useful and shows the ball valve:
https://airgunwarriors.com/community...le/#post-55186

Don R.