My first effort at taking apart and working on a spring air rifle

[HeadDamage]

My Air Venturi rail lock spring compressor arrived so I had a go at stripping my first springer apart. The first victim is my new WF600 with about 100 shots through it.

The compressor worked great for taking it apart. The seals in the otherwise new gun looked like they had been put through the wars. There were a few metal flakes stuck into the piston seal face and both it and the breech seal were much harder and warn looking than the replacements.

The new spring is about 1.25" longer than the stock spring which seems odd as this is a rebuild kit for the gun not an upgrade kit. I bought the kit with the rifle.

This is the kit I used (didn't use the piston, screw, or the seal retainer).
https://canadashootingsupply.ca/product/wf600-repair-kit/

I cleaned it all up, installed the new seals, put molly where I think is supposed to go then it all came off the rails. When I tried to put the compressor back on the rifle the bolt that squeezes it together to clamp on the dovetail seized. There wasn't even any pressure on it yet, looking closely there was a bit of tread coming out of the junction between the bolt body and the compressor. I have no idea how the tread bailed like this with no load on it. The bolt absolutely refuses to turn. I guess I'll call Canada Shooting Supply on Monday and see if they will warranty it or if I'm going to get the saw, drill, tap, what ever out and try and fix it.

I've attached some photos of the parts from when I was happy and making progress.

 

[HeadDamage]

Turns out that if you weigh 300lbs and you are creative enough you can reassemble the spring into the gun without a spring compressor. It was not easy but it is in and the gun is together.

Success! It cocks, the anti beartrap works, the safety works, and it fires.

For some reason the trigger is now good though it acts like a set trigger followed by a crisp very short throw trigger. When you start to pull it moves back with a click, then you can let go and it stays primed so to say. The second stage is very crisp now, not too light but crisp with not much movement. So much nicer to shoot now. All I did to the trigger was rub the pieces around in my molly stained hands before reassembling them.

The gun feels nice when shooting now, still has a bit of twang but it sounds mild. I've fired 170rds so far and the accuracy seems good, better than it was. I kept the chamber oil free as possible and there is no detonation and just a wisp of smoke from the barrel when opened.

I did need to shim the side stock screws with a couple of washers each, without the added washers the screws protruded far enough to block the cocking mechanism.

Velocity, oddly, seems a hair lower than before but more consistent. Formerly it was averaging 460fps (Crosman 14.3gr) 14.3gr pellets now averaging 455.6fps and the Crosman alloy 9.5gr pellets are averaging 600.2fps.

I am curious as to how the longer spring with more coils resulted in almost the same energy but possibly nicer shooting characteristics.

Asside from the gimped up compressor I'm very happy with the results

 

[ronaldharold]

After 500 or so shots, the gun will get smoother, and sometimes gain a few feet per second

 

[IanC]

My first was a diana 34 and I built a really crude compressor for it. The job was easier than I thought it would be. My last one was an HW80 and the spring was a real pain to get in. Springs are generally longer before they go in since being in the gun gives them a set over time. Odd yours has extra coils unless it is a general spring that fits in several rifles of the same guy. Don’t make the same mistake I made by telling your shooting buddies what you did they will want their guns fixed too. Lol