FWB 600 recondition

[NTSOG]

G'day all,

I received a kit of new seals for my FWB 600 [SN 67**]. All parts fitted easily except the new cylinder bushings [Buchse in German]. Both were too thick and made of plastic so I could not replace the piston with them in place, whereas the original bushings are much thinner and might be a coated metal [???] The rifle is now firing beautifully: 555 fps, Spread about 7 and Sd 3.

My question is: did FWB change the specifications of the cylinder and, hence the size of the bushings at some point? [I am assuming that the rifle is quite an early one of its type, but I have not been successful in finding out the date of manufacture so far.]

Jim

Ballarat, Victoria, Australia

[wonky donky]

The piston bushings were changed from a sintered material to plastic which should be a straight forward replacement. The cylinder configuration was changed with the introduction of the 602 but not in the way your asking.

Hope this helps

Dave

[NTSOG]

Thanks Dave,

That is a help.

I can install the plastic bushings easily on the piston. However I was not prepared to force-fit the piston with the plastic bushings into the chamber - I doubt that the assembly would have gone in anyway. The fit with the old sintered [Thanks for clarifying that.] bushings is close and seems operationally "stable" and, hopefully, they are not going to damage the inside of the chamber. The newer plastic bushings would be over twice the thickness of the sintered. I will have a chat to the distributor today. I may just have to purchase a new piston body.

Thank you,

Jim

[wonky donky]

Hi Jim, I've never had any new piston bearings (bushings) that were tight, & I've fitted a few. Are they genuine Feinwerkbau? Are you able to take any off the "split" so they will close down into the grooves more or is the i/d correct & the o/d oversize? just a thought. They don't want to be tight or sloppy either but as long as there's sufficient thickness to stop the rear of the piston rubbing the cylinder on the compression stroke that's fine.

Dave

[NTSOG]

Hi Dave,

The new plastic bushings fit around the cylinder, but the ends do not meet - the gap is perhaps 10mm or so like the bushing on my Walther LG 90 which is an incomplete "circle" around the piston. The i/d is apparently correct, but the depth of the bushing is excessive thus making the installed o/d too great. The old bushings wrap completely around the piston and the ends meet exactly.

The parts come from the main FWB importer and have the correct part number on the pack - but that does not mean that there was not a swap by mistake.

-------------------------------------------

Hi Dave,

I spoke to the importer this morning. He says my rifle is one of the very early ones and he cannot get sintered bushings anymore. I will have to buy a new piston which will take the plastic bushings. In the meantime I will just have to check that there is no undue wear on the inside walls of the compression chamber.

Thank you again for your help,

Jim

[Maciek]

Hi . some time ago I've got smmilar problem with parts to My FWB C60 .
Feinwerkbau it has all of the parts to all models .
Try
http://www.euroshooting.eu
or directly Feinwerkbau
http://www.feinwerkbau.de/en/Service...loded-drawings

Write what You need and rifle No. They always happy to help .

[NTSOG]

Hi Maciek,

I will keep that in mind. Following the advice of Dave [wonky donky] I have had a good look at the clearance between the inside of the compression chamber and the piston body. With the old bushings in place there is equal clearance all the way around. There is also no indication of the piston, especially at the rear, shifting to one side or another as the cocking lever is closed. In fact the clearance on the FWB is slightly greater than the clearance on the piston in my Walther LG90 which has been fully rebuilt.

Thank you for your advice,

Jim