FWB 103 - New Owner, Charging Question

mbdslpwr · Post by **mbdslpwr** » Thu Sep 08, 2011 5:02 pm

I was able to acquire a very lightly used FWB 103 recently, and want to put it back into service.

Upon receipt, I gave it a good look-over, cleaned up some of the dirty spots from sitting, then checked the lubrication. All seemed well.

When I charged it for the first time, the outswing of the charging lever was pretty smooth, save the last couple inches of the stroke. When I actually charged the pistol, it felt rough, as though a seal were lacking and two surfaces were rubbing.

Does anyone know what could be wrong here / how to correct?

Considering this is a -really- nice pice of kit, I'd like to ask for help (possible problems and solutions) before I try to work on it myself.

Any help is appreciated.

Thanks!

MBDSLPWR

supraphonic · Post by **supraphonic** » Thu Sep 08, 2011 5:51 pm

Hi,
If this pistol has had the seals replaced it could be that the barrel/cylinder housing is slightly out of alignment, slowly open the charging lever to see if it is rubbing anywhere . The clearance between the Barrel/Cylinder housing to the charging lever linkage mechanism is very fine any rubbing will make the noise that you have described. I had this same problem after disassembling my FWB 100. The solution is to remove the end cap
at the mussel end, lossen the screws that attach the housing/shroud
around the barrel & cylinder ,realign everything so that the cocking mechanism doesn't rub on any thing, This fixed my problem , it is a little tricky and may require several attempts. You could actually see small particals of aluminum on my gun where it had been rubbing.
Sorry I havn,t explained better but, I bet this is what you problem is.
Cheers.
Paul.

Rover · Post by **Rover** » Thu Sep 08, 2011 6:01 pm

It could just need a little lube, expecially if it's been sitting a while. As you say, they are a nice piece of kit.

kevinweiho · Post by **kevinweiho** » Thu Sep 08, 2011 8:42 pm

If the pistol was not used for a long time, it could be possible that the seals have rotted or in need of proper lubrication.

What lube are you using?

mbdslpwr · Post by **mbdslpwr** » Thu Sep 08, 2011 9:27 pm

I applied a thin coat of the FWB special grease which came with the pistol. I followed the manual's instruction to brush a light coat of grease on the air-piston and guide surface. This mitigated the rough cocking somewhat, but not completely.

I took a few shots with it in this condition and compression / power felt very good. Not chronied, though...

kevinweiho · Post by **kevinweiho** » Thu Sep 08, 2011 11:51 pm

mbdslpwr wrote:I applied a thin coat of the FWB special grease which came with the pistol. I followed the manual's instruction to brush a light coat of grease on the air-piston and guide surface. This mitigated the rough cocking somewhat, but not completely.

I took a few shots with it in this condition and compression / power felt very good. Not chronied, though...

If the power seems O.K., how does the pistol group?

If the cocking continues to be rough, then a disassembly of the charging mechanism is necessary as Supraphonic had stated.

You can find the exploded diagram of the FWB 103 and other models from their website: www.feinwerkbau.de/

mbdslpwr · Post by **mbdslpwr** » Fri Sep 09, 2011 5:29 am

Went to the website yesterday and pulled down the manual and parts diagrams, too. I will look into the disassembly a little closer today.

Grouping is hard to tell, though much more on account of the person pulling the trigger.

Thanks for the assistance.

MBDSLPWR

Cones · Post by **Cones** » Sat Sep 10, 2011 9:10 am

Hi,

I wrote a complete strip guide with photos for my FWB 100. The 103 is very similar.

See here.

http://www.airgunbbs.com/showthread.php ... -Model-100

Thanks

Mark

mbdslpwr · Post by **mbdslpwr** » Sat Sep 10, 2011 9:15 am

Hey - thanks. I'll review this over the weekend and perhaps dig into the gun a little further.

--Ok, I got impatient and disassembled the pistol per guide above. Removed the air piston / charging assembly, wiped out the cylinder walls, wiped off the piston, seal, adjusting ring, etc. then re-greased them with FWB grease, then reassembled the pistol.

And damn, if those oval head screws behind the holder at the muzzle weren't tight. I nearly stripped the head off one trying to unscrew it. Be careful, there!

Upon reassembly, I charged it and took a few shots. The charging stroke feels smoother and even, no more high/low points. But the sound is still there. Now, I could be expecting too much by way of silence. A rubber seal sliding, with pressure, across a glass-smooth surface is one thing. But the aluminum cylinder's interior walls in my pistol are -not- glass smooth. They're more a matte polish, if that makes sense, so maybe it's fair to expect some sound on the charging stroke...

MBDSLPWR

Cones · Post by **Cones** » Sat Sep 10, 2011 11:00 am

Hi,

No Problem.

Yes, the walls on my FWB 100 are not polished smooth. I suspect the non smooth finish retains some of the grease and this along with the piston seal is what allows it to retain the good seal over thousands of operations.

Now you have cleaned and lubed it it will probably feel better after a few hundred shots or so.

Thanks

Mark

mbdslpwr · Post by **mbdslpwr** » Mon Sep 12, 2011 5:39 pm

I received re-verification from the previous owner that (a) he purchased the pistol new several years ago and (b) shot perhaps a hundred pellets through it.

So, guess I'm the one who's really going to break it in. Excellent.

MBDSLPWR

TargetTalk

FWB 103 - New Owner, Charging Question

FWB 103 - New Owner, Charging Question

FWB Special Grease

Re: FWB Special Grease

Disassembly

Excellent - Thanks!

Great News!