FWB 602 - Two rifles, two problems

[Mtl_Biker]

By coincidence I have two different problems to report and ask for help with, on two different guns. Tonight a friend and I had planned on shooting my FWB 602 for a little friendly match and there was a problem and we weren't able to shoot it. I arrived home with the intention of coming here to ask for help and in my email was a message from the president of our local rifle club telling me about a problem with the club's 602 and asking me (since I also own one) if I might be able to come here and try getting some advice. So, two rifles, two different problems. SIGH

FWB #1 (Mine): Bought it used two months ago and was assured (by a reputable and experienced dealer) that all the seals were in perfect condition. I've shot about 3,000 pellets through it without issue. Last night during some shooting it sounded like a couple of shots were under-powered but that was only about two shots out of 60 and the problem didn't seem to be serious. Well, tonight we weren't even able to get one shot out successfully. The gun goes pffft, and the pellet falls far shot of the target. Shooting without a pellet the sound is just about normal... perhaps a little less strong. Put a pellet in and shoot, and it just goes pffft and the pellet falls to the floor. Nothing sounds or feels unusual during the cocking/loading process. I have no idea what to check or really even how this gun works internally. And I don't have a manual with the gun.

FWB #2 (the club's gun): Here's what I understand... There's a report from an experienced member that the 602 has an odd sound after it has been shot and is re-loaded. The president looked at it and it seems that once the shot is fired, and upon going through the motion of loading the next round there is a distinct pop when the crank-lever is moved, It sounds like there is still residual air pressure after the shot and it escapes at the moment the loading lever is moved. The same puff sound also occurs when the dry-fire lever is pushed forward to reset the trigger and as soon as the trigger is pulled, that residual air passes through to the barrel.( at a much lower pressure).

This second gun/problem sounds very much like the one being reported here with a model 601 FWB, which doesn't seem to have been resolved yet.

Any chance that there's a technical manual for these guns to be found somewhere? Any ideas about either of these problems and their solutions?

Thanks very much for any help.

[Doodaddy]

Rifle number two has what is apparently a reasonably common problem for these rifles from what I've seen searching for a solution. What solved it for everyone else (new seals) didn't help me though that's where I would start on both of the rifle if I were you. Since rifle number 1 sounds normal dry firing, but a shot pellet has virtually no velocity, it sounds like a seal is busted somewhere.

For whatever it's worth, I believe my issue has been resolved with using a stronger firing pin spring.

Exploded drawings:

https://www.feinwerkbau.de/en/Service+D ... d-drawings

Manual:

https://www.feinwerkbau.de/en/Service+D ... duct-range

[Mtl_Biker]

Rifle number two has what is apparently a reasonably common problem for these rifles from what I've seen searching for a solution. What solved it for everyone else (new seals) didn't help me though that's where I would start on both of the rifle if I were you. Since rifle number 1 sounds normal dry firing, but a shot pellet has virtually no velocity, it sounds like a seal is busted somewhere.

For whatever it's worth, I believe my issue has been resolved with using a stronger firing pin spring.

Exploded drawings:

https://www.feinwerkbau.de/en/Service+D ... d-drawings

Manual:

https://www.feinwerkbau.de/en/Service+D ... duct-range

Thanks very much for that!

I've worked on springers before but never an SSP... do you know of anywhere I might find instructions about how to change those seals? Or any other how-to information that may help a novice like me?

[kevinweiho]

I've worked on springers before but never an SSP... do you know of anywhere I might find instructions about how to change those seals? Or any other how-to information that may help a novice like me?

Here's a video on how to disassemble/reassemble and replace the seals on the FWB 601. Compared to the 602, they are very similar. It's a bit more trickier than changing the seals on a springer.

https://www.youtube.com/watch?v=F67Yg6EXUjo

https://www.youtube.com/watch?v=lkjzsoSPSVE

[Mtl_Biker]

I've worked on springers before but never an SSP... do you know of anywhere I might find instructions about how to change those seals? Or any other how-to information that may help a novice like me?

Here's a video on how to disassemble/reassemble and replace the seals on the FWB 601. Compared to the 602, they are very similar. It's a bit more trickier than changing the seals on a springer.

https://www.youtube.com/watch?v=F67Yg6EXUjo

https://www.youtube.com/watch?v=lkjzsoSPSVE

Thank you, Kevin!!! Very helpful. Now if only I could understand the German narration.

[SlartyBartFast]

If the problem can't be resolved without some knowledge of German, I know someone who worked with me and who was very much a gun enthusiast who was quite fluent in German and translated a few of our technical manuals from German to English for North American clients.

Haven't seen or talked to him in years, but I could always try.

[Mtl_Biker]

All is good now! Thanks guys for your suggestions.

I sent my FWB 602 to Cibles Canada Targets (www.targets.ca) and they received it yesterday. It's already fixed and on the way back to me. Two new seals... a green one and a main valve seal replaced. The rifle's now shooting a consistent 580 fps.

Total cost, including overnight return shipping to me was $72 Canadian!!! Fantastic service from Cibles and all my dealings with them so far (about 20 times) have gone extremely well. They know their stuff and are reliable, prompt and honest. Kudos to them! (And they have an eBay store for all kinds of great stuff.)