My new fwb 600 is a bit rough 😂

[marflow]

well it is a crime scene for sure
the stock can be fixed with hard work
the metal is another story
i think powder coat would be the goal
the pitting is the problem if it was one spot you would weld and smooth
so there are enough parts to cover the £90
i would not sand any of the metal have it soda blasted or something gentle the time saved will be worth every penny
the bad spots could be brazed but in the end it will need a coating not blue
keep us in the loop and don't be in a hurry but stop the rust

 

[MikeyB]

Be sure to post some pics of the refurbished gun, I reckon everyone would love to see what you can do with this one.

 

[mike8]

Of course i will update you guys in this restoration. At work i do a lot of rust removal. Sometimes it feels half my job is about removing rust and preventing rust. So i have some experience with this. I'm fairly certain i can get this one looking fairly good and original again.

 

[junglie2022]

90 €. Was asking about the sights that a guy sold for 45€. Said it was from a 600. I asked if they would fit a 300s without modification. Guy says i can have the whole gun for 90. And he also said that it looks like hell. That he had never seen anything worse. Challenge accepted!

Not too bad then,the diopters probably worth that alone.

 

[mike8]

So i had a bit of bad luck. While trying to bang out the barrel from its little stainless block i managed to damage the rear cone!! Its now a bit bent and warped. So now i need to find out what angle that cone has. So i can turn a new one.

Had to press out the barrel.

Also after sanding the barrel in the lathe i figured it would be a good idea to simply turn it down 0,2mm or so, to speed things up. And while doing that i managed to simply run the tool into the barrel instead of backing the tool up towards the chuck. So i had to shorten the barrel.

But it was only an empty tube anyway. A shroud. About 20cm of it! So yeah bye bye excessive shroud.

I finished sanding the stock at least.

 

[mike8]

 

[Scott3131]

View attachment 1018997

Is that a self portrait

 

[mike8]

I also found out that this gun will never be really nice ever again so i'm just gonna do it as good as i can. Not trying to keep original finishes and so on.

I mean the flip up loading lid is a bit rusted. It looks like stainless but its magnetic. So either its ferritic stainless, duplex stainless or martensitic stainless. But i'm 99,9% certain its none of those materials. Its just chromed carbon steel.

And i'm not gonna rechrome anything on this gun. And there is about 10 other similar things.

So i'll just make the best out of the situation. Thats it. I wish it was in better shape but its not.

 

[mike8]

Trying to calculate angles for conicity of the barrel interface. Measuring:
bottom diameter 6,6mm,
top diameter 11,7mm
Depth 5,50mm
Need an angle to cut on the barrel.
I can adjust start/stop diameter.

Actually thats exactly what i will do.
When i have the angle i just cut at that angle and move in until i reach the biggest diameter of the barrel. Will cut the groove for the oring first.

 

[mike8]

I need to cut at this exact angle

 

[marflow]

you don't need my help but i would one thing first if you haven't already
go to Feinwerkbau and i will leave the link and take the parts diagram and then take inventory
the barrel end that looks damage did seal with an O-ring i would first straighten the breech barrel end first
your work will never end on that rifle i have been there done that you will have a hard time knowing when to stop and at some point you will wonder why you ever started been there also
https://feinwerkbau.de/en/service/downloads/technical-information/exploded-drawings

 

[mike8]

So i took some measurements with my mitutoyo caliper, sure they are only good for 0,1mm or 0,05 if you have good judgement. But in this case i'm just eyeballibg stuff in different light trying to get a close approximation. Although i do have education in mechanical measurements, i used to work as a a machinist.

So i feel the numbers i got out of the mitutoyo is as good as i can measure stuff like this with a caliper.



So i took measurements of the dented barrel and also the breech. This is what came out of that.




Fairly certain the angle i want is 24 degrees.

 

[mike8]

you don't need my help but i would one thing first if you haven't already
go to Feinwerkbau and i will leave the link and take the parts diagram and then take inventory
the barrel end that looks damage did seal with an O-ring i would first straighten the breech barrel end first
your work will never end on that rifle i have been there done that you will have a hard time knowing when to stop and at some point you will wonder why you ever started been there also
https://feinwerkbau.de/en/service/downloads/technical-information/exploded-drawings

I will machine a new end on the barrel. Then shrink it in, then order all seals. And then maybe fabricate 1 part. The black plastic one you see in the pics above. I'll just make it out of alu, i will make it with an angle grinder/hacksaw/file only place that have ot in stock is gotha and they are on vacation now for a month i guess. So i have to make that part.

The barrel end was good until a couple of hours ago when i started banging on it when i should have just used the press from the start. Now its not good anymore. Need to make a new barrel end.

 

[mike8]

The measurements hover around 24 degrees. If i go higher like 25 i can get stuck half way down before i reach the bottom. If i go lower. 23 degrees the o-ring will probably absorb it. Still suboptimal. But it will probably work. As long as i have the minimum diameter of the seal seat on the barrel and then the biggest diameter of the cone on the barrel.

 

[mike8]

As long as A and B is correct and the angle is lower (a slight amount) or just the same as original. I think this will work. This how the barrel looks.

 

[mike8]

Made 2 test cones. 24 degrees and 25 degrees. Put some paint in the alu mating part.
Looks line 24 degrees is it.

 

[mike8]

The repair was successful. I made an identical end. Alu cone piece goes all the way back. And no side to side wobble when its bottomed out.

 

[mike8]

So i guess this means that i actually can repair this gun.

But now i'm thinking about what finish to put on this barrel. Both the barrel and compression tube have pitting which i will not be able to remove.

Also on the front og the tube is a double ring that squeese on both parts. And that one will probably scratch up any regular paint.

Is there any ceramic pain like ceracoat that doesn't need heat to cure?

Also hot bluing may not be an option here.
Supposedly barrel sleeve is glued on. And also supposedly compression tube is glued to the stainless block.

And from what i have read cold bluing is some selenium compound that just turns black on the surface. It need to be better tha that i suppose. Because i don't want to press this crap apart ever again.

 

[mike8]

So i'm trying out if i can get a usable surface on steel. First hcl at around 3% its gonna go light gray. I know how looks at 35% and yeah you get a gray color.



Then oxalic acid. I just mixed in a bit of poweder in water. The part turns very dark gray/black very quickly. I took this one up and polished it with 1500 grit scotchbrite. There is still a gray color left. So this will work. This is durable.

Then after half an hour a white/green coating appears. I just wiped it off. Also put it ammonia and wiped it. Still gray. This is how it looks after 1 sanding after maybe 5 min soak. Then ammonia and wiping after 30 min soak. This oart was almost black after 5min. But i polished it.



This is a part i did many years ago in oxalic. Its almost black. Tried scratching it with a drill bit. And yes the very dark color can be scratched off but there is still a dark color under that, that will not scratch off. Also the oxalic stops working quite fast. So after about half an hour it has no effect anymore. Then you will have to make a new bath.

 

[mike8]

From left to right. Low conc hcl, oxalic, ammonia, ammonia/naoh, reference/nothing

Oxalic gives a cool gunmetal gray imo. So i'm gonna go with that.