Originally Posted by dvd
The seals are made of some synthetic material, very similar to what is commonly used in most guns, so no problems in sourcing them.
I buy my parts from Waffen Gotha in Germany, good people to deal with and good prices too. They do a complete overhaul kit for the Mod 75.
When the velocity starts to fall off below 400 fps, it is time to renew the seals with the modern blue ones. Do not go on shooting the gun in this state because the deterioration of the seal effectively alters the timing of the pistons and you risk damaging the pistons and gears.
Otherwise with new seals in place, they are good to go for many many years.
This is all nappy filling stuff!
I'm going to stop shooting them until they're sorted.
My breech seals look like a very worn out versions of the pictured " luftdichtung " in the service kits on the Waffen Gotha site. I assume the breech seal in the photo is the old material ie not blue ? I'd guess the breech seal can be changed any time without stripping the gun so anything is better than nothing. Tom will be servicing my guns at the Air gun clinic local to me. He knows his onions so I'll liaise with him on the best route to take.
Shame my FWB 300 S breech seal failed the other day ( its in two halves ) .
Edit ; I've had an idea !!
I wonder if it would be possible to turn out some breech seals ( blue ) using either the piston or buffer seals as donors ?
Is there enough meat to pop it on a lathe if the dimensions were taken from the Diane breech seal ?
Just a thought.
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