I don't know if you remember me but I purchased a GRTIII trigger and installed in a refurb. Gamo Hunter 440 bought from Cabelas. I've had lingering problems with scope creep and was plagued with inconsistent accuracy which I attributed to my ignorance of springers.
Friday the cocking cycle started feeling rough and then p.o.i. abruptly raised some 100+ clicks at 10 yards. I was thinking a broken spring but still unsure so shot a few times attempting to rezero ... then noticed that Bushnell 4-12X elevation turret had moved inward. I stopped shooting, removed failed scope, replaced with a 4X and was able to rezero with a few shots, however I found this scope was at absolute minimum elevation setting after rezeroing.
I decided to try and locate real source of my problems. I disassembled rifle including the trigger ... then I found out the trigger can be removed as as an assembed component...! What I found after removing a lot of grease was a main spring was in three pieces and a piston seal with a deep notch that had eroded from 0.06 on face to 0.30 on back side of seal. I know about when spring failed last but I suspect seal may have been damaged for quite a while, am also clueless when first spring failure occurred. OBTW this 440 has less than 2,500 shots since I purchased refurb.
When I first bought rifle I shot through my Chrony Beta and both Crosman wad cutters and Gamo domes were in 890-930 fps range. Sure wish that I'd shot through chrono again prior to disassembly. How this rifle ever grouped at all remains a complete mystery to me !
I have a few questions:
1. Does someone know if Gamo will sell service parts to a customer?
2. If not then where can I source parts I need to rebuild: seal (12540), main spring(16090), 3-diameter plastic collar (16320), fore-end screws (16350), cocking roller (14300)?
3. Does anyone have experience and/or assembly jig to re-assemble trigger that I have disassembled? I'm not at all confident about putting it back together.
Update: We have a new grandson born last Friday in Durham, NC. We're leaving to go see him next week so will be back East where it seems many GTA forum members are located.
Curtis aka Reloader
Irvine, California
