Annie 250 strip show horror!!!

[tinbum]

This will go on a bit. Just saying!

On Saturday I got a 250 match as a spares or repair kinda thing. The cocking lever was stuck open for reason/reasons unknown. Fortunately, I was at the Springer Bash and surrounded by more anoraks than Millets front window.

As soon as the bag was opened some 1970's airgun pheromones wafted gently downwind and attracted a Jon Budd who arrived horny and ready for some action! Afte a bit of prodding and poking, it was discovered that the anti bear trap release catch was operating at the wrong moment. We adjusted it and it worked for around a dozen shots, then the same thing happened again.
A quick strip later and we could see the problem, but not how to solve it? Eventually we just put tape over the bear trap so it could be used for the day.
Heres some pics, if anyone has any info I'd appreciate it.

http://i279.photobucket.com/albums/k...psl276dpnh.jpg

http://i279.photobucket.com/albums/k...pszgl27pqs.jpg

So, with that problem bodged it was time to shoot it. Nightmare! Couldn't get a group, then pellets stopped coming out altogether! It went back in the bag until this afternoon when I finally got a minute to strip it.
First thing I noticed was the lush, furry velvet effect on the hydraulic damper unit.

http://i279.photobucket.com/albums/k...pscpk0dp20.jpg

A quick spin in the lathe polished that off though.

http://i279.photobucket.com/albums/k...psu2acl2w3.jpg

I removed the drain screw to pour out any remaining ATF. Nothing! So I took the unit apart and it was packed full of grease! The seals are made of crumbly cheese and there was an e clip missing from the damper rod, so the whole unit had been totally inneffective.

http://i279.photobucket.com/albums/k...psxifqom6x.jpg

http://i279.photobucket.com/albums/k...ps6a1lqcma.jpg


On stripping the piston (skirtless, so much for innovative, new ideas) I found the comp tube was full of rubber debris, which is all that remained of the piston buffer. The Breech seal looks just as bad, so I am getting a new set of seals before I start rebuilding. That gives me plenty of time to clean and polish everything.



If anyone has any ideas about the ABT I could do with the advice.

[Shed tuner]

ref the ABT.. as the notch is fixed, the one thing that dictates the position of the rod that passes through the ABT is the engagement with the piston / comp tube. At a certain point the comp tube moves independently of the rear carrier.. so if the interface / overlap at which they part company can be tuned to happen earlier, then that rod with the big notch will stop moving forwards earlier - and not bugger up the ABT. Maybe just sticking it all together properly, with the circlip etc might just sort it enough to get into the adjustment range of the little slider that blocks off the ABT ratchet.

Piston washer looks great.. I had an FWB like that too. Interesting on the damper...

[Garvin]

If anyone has any ideas about the ABT I could do with the advice.

I did a refurb of one of these dampers years ago here if it's any help?

I can see from your pics that a washer behind the damper unit that was originally made of cork (?) I think, has perished. Waffencenter Gotha do replacement ones in quite hard plastic, which you could reproduce.

[tinbum]

ref the ABT.. as the notch is fixed, the one thing that dictates the position of the rod that passes through the ABT is the engagement with the piston / comp tube. At a certain point the comp tube moves independently of the rear carrier.. so if the interface / overlap at which they part company can be tuned to happen earlier, then that rod with the big notch will stop moving forwards earlier - and not bugger up the ABT. Maybe just sticking it all together properly, with the circlip etc might just sort it enough to get into the adjustment range of the little slider that blocks off the ABT ratchet.

Piston washer looks great.. I had an FWB like that too. Interesting on the damper...

I will get back into checkng that in the morning. It must be something thats obvious once you've found it.

[tinbum]

I did a refurb of one of these dampers years ago here if it's any help?

I can see from your pics that a washer behind the damper unit that was originally made of cork (?) I think, has perished. Waffencenter Gotha do replacement ones in quite hard plastic, which you could reproduce.

Is that for the rear of the unit where it abutts the end cap?

[Garvin]

Is that for the rear of the unit where it abutts the end cap?

Yes, that's the one.

I just found a much better damper rebuild pictorial than mine. You can see the washer at 2.08.

[wonky donky]

Nick from what I can see the safety parts look complete so I'm guessing the problems a minor one of dirt or adjustment, without having the unit here I can't say more from the pics.

Okay this is how it works.

The compression tube when drawn back just contacts the abt button & you will hear the clicks.

Toward the end of the levers travel you will feel slightly more resistance, this is when the unit towards the trigger behind the abt is picked up.

Almost at the very end of the cocking stroke the silver bar the ABT sits on passes through. ( will notice a cut out on the silver bar) the unit with the screws is picked up by the end of the cut out (theres a tang on the unit with the two screws) & the tang the other end is pushed into the recess on the button. pust the ABT button down you will see it.

On the forward stroke of the cocking lever towards the end, the other end of the cut out engages the unit with the two screws pushing it forwards thus releasing the ABT.

Hope this helps
ABT Dave

[tinbum]

Yes, that's the one.

I just found a much better damper rebuild pictorial than mine. You can see the washer at 2.08.

Thats the fella I'm getting the service kit from. For the cork washer I'm going to make two very thin delrin washers with a smear of silicon sticking them together for some shock absorbancy.

[Benelli B76]

I just love 'em these Star Wars rifles. Especially the way the whole trigger block removes intact, why don't they all strip like that, and of course the lovely way they shoot.

Baz

[Shed tuner]

I just love 'em these Star Wars rifles. Especially the way the whole trigger block removes intact, why don't they all strip like that, and of course the lovely way they shoot.

Baz

Yeah, the trigger casette removal was nice and easy; great design. Also meant we could de-cock the thing when it jammed. It even has a design such that should the casette move away from the rifle, it wouldn't actually fire... Really clever.

Nick from what I can see the safety parts look complete so I'm guessing the problems a minor one of dirt or adjustment, without having the unit here I can't say more from the pics.

Okay this is how it works.

The compression tube when drawn back just contacts the abt button & you will hear the clicks.

Toward the end of the levers travel you will feel slightly more resistance, this is when the unit towards the trigger behind the abt is picked up.

Almost at the very end of the cocking stroke the silver bar the ABT sits on passes through. ( will notice a cut out on the silver bar) the unit with the screws is picked up by the end of the cut out (theres a tang on the unit with the two screws) & the tang the other end is pushed into the recess on the button. pust the ABT button down you will see it.

On the forward stroke of the cocking lever towards the end, the other end of the cut out engages the unit with the two screws pushing it forwards thus releasing the ABT.

Hope this helps
ABT Dave

hi Dave, yeah, we sussed it out (but you'd have saved me 30 mins of deduction if you were there ! )

However the problem is that on the return stroke, the slide that nudges the ABT back into play gets pushed out by the notched rod too early, preventing closure of the lever. So we adjusted the slide using those two litte screws, but then it wouldn't releas at the begining of the retrun stroke. In the middle kinda worked sometimes, then not at all.

So I think that the problerm is the dog that pushes the notched rod backwards and forwards is being pushed slightly too far forwards before it is "left behind" by the comp tube - something to do with the interface between the comp tube and the rear part of the mechanism...

[wonky donky]

So I think that the problerm is the dog that pushes the notched rod backwards and forwards is being pushed slightly too far forwards before it is "left behind" by the comp tube - something to do with the interface between the comp tube and the rear part of the mechanism...

The compression tube doesn't push the dog forward Jon.

The steel part of the damper unit that has the spring guide in it at the front & the cone that slots into the "T" of the alloy damper all move forward at the end of the forward stroke of the cocking lever.

Forward of the delrin bearing on the steel part is a cut away about 15mm wide & 10mm deep, it's this that contacts the dog, you will feel it being picked up when closing the lever.

It wouldn't hurt to strip & clean the whole of the trigger assembly, especially the steel bar. Any imperfections or contamination can cause problems.

Have some more of your life back on me! keep well.

Best of luck Nick, the rifles well worth doing but make sure it's right as the rear of the action, where the pin goes in< will break away making it scrap if the dampers not working properly.

ATB Dave

[Shed tuner]

Cheers Dave, makes sense... yeah, it's the rear untit that pushes the dog forwards, before the comp tube then just carries on on it's own at about halfway through the return stroke... I think Nick will have to look in that area.. might just be a case of too much crud in there (there was plenty !)...

[Benelli B76]

[QUOTE=Jon Budd;7076075]Yeah, the trigger casette removal was nice and easy; great design. Also meant we could de-cock the thing when it jammed. It even has a design such that should the casette move away from the rifle, it wouldn't actually fire... Really clever.

I have always believed the Germans were good engineers, and safety is at the top of their agenda ! Another point I have found is that there are seals available for the damper unit that are too long when you fit them in the recesses. You do not realise this until you try to strip the rifle again and you cannot separate the "T" lock.

Baz

[tinbum]

Ta-Daaaaa!!!

http://i279.photobucket.com/albums/k...ps7rjlke8k.jpg

My hydraulic service kit, piston buffer and breech seal arrived today, so it was back on the bench for a rebuild. The central rod in the unit was missing a C clip, that meant it wasnt moving the way it should. Thinkng that tgrough I worked out that was the reason the ABT actuator was all over the shop!
Everything has been cleaned, polished and relubed with hi moly paste and the difference is amazing! From a lurchy, crunchy cycle which barely moved the pellet up the barrel its changed to a smooth yet sharp recoilless cracker thats pushing JSB's out at 7.8ft/lb and Hobbies at 7.2ft/lb

With parts and bipod it has cost me £216, and now its serviced it should be ready for another 50 years of use.

[Shed tuner]

Good result