Recently picked up this real nice 1973 vintage HW 35 at a local gun show. This rifle sparked my interest to get into airguns
The original leather breech seal needed replacement for sure, so I also decided to install a new spring kit.
Since I never took a air gun apart I searched the forums and youtube and found lots of helpful info on how to do it.
The rebuild went pretty smooth. I wanted to go with 25 coils but had to go with 24 because I couldn't compress 25 coils enough to screw the receiver back together,
I kept the original leather piston seal as it was still in good condition.
Here is some interesting data using 8.2g pellets 10 shot strings
As bought, with no breech seal- it shot 483 fps
+ new breech seal it- shot 604 fps
+ new 24 coil spring and needs-foot oiled leather piston seal- it shot 766 fps
A 283 fps improvement and I am guessing it may go up a little as it breaks in
The original leather breech seal needed replacement for sure, so I also decided to install a new spring kit.
Since I never took a air gun apart I searched the forums and youtube and found lots of helpful info on how to do it.
The rebuild went pretty smooth. I wanted to go with 25 coils but had to go with 24 because I couldn't compress 25 coils enough to screw the receiver back together,
I kept the original leather piston seal as it was still in good condition.
Here is some interesting data using 8.2g pellets 10 shot strings
As bought, with no breech seal- it shot 483 fps
+ new breech seal it- shot 604 fps
+ new 24 coil spring and needs-foot oiled leather piston seal- it shot 766 fps
A 283 fps improvement and I am guessing it may go up a little as it breaks in