The Jesus Circlip - AA S200 / Avanti XS40 / CZ200
Posted: Sun Feb 05, 2017 5:25 pm
Many of you who shoot the S200 may not even know about this component that sits at the centre of the action in this rifle. It is so tiny, so difficult to get to and so awkward to work on that folklore and legend among fettlers has earned it the name The Jesus Circlip. This is so because apparently you will call out His name many times as you struggle with the circlip trying to get it in or out. I have to say here that other gods' names may work just as well like Buddha, Allah, Krishna etc. etc. cos we are an inclusive forum ... 
Sorry Jain members ... but somehow I dont think Thirthankara Wardhamana Mahavira would work in this context. 
See below, the circlip next to the end of a biro refil for scale.
Here is a bit of information about it and a way to tackle it that I came across while doing Rob's rifle this weekend.
Where is it and what does it do?
It sits on the Striking Pin (No.40) and holds it in place within the Receiver Body (No.13) - to stop the Striking Pin Spring (No.41) from flying out when the air cylinder is removed. See below.
You can't even see it till you have turned the Body upside down and removed Part Nos. 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 and 92 out of the way.
Once you have removed them, you need to push the Striking Pin in against the Striking Pin Spring from the front end and look through the slot in the Body provided for housing the trigger assembly.
So how do you work on it?
Well, using a bit of logic I figured out that if I screwed the End Plug, Firing Valve (No.38) back into the Receiver Body, it should push the pin into view. This it did, but not enough to be able to get a grip on it.
So I took some 6mm Dia. bar I had lying around and cut off a length of 5mm. I cleaned this free of burrs and dust, made sure the faces were square to the length and placed it between the end of the Striking Pin and the Firing Valve Gate (No.37) before screwing the Plug into the Body. The power of the Valve Spring (No.35) is clearly way more than that of the Striking Pin Spring and so the pin is pushed and comes more clearly into view allowing you to approach the circlip with a set of slim long nosed pliers. The picture below is heavily enlarged. You can see the groove on the pin where the circlip goes.
When and why would you need to remove this?
Almost never. The Striking Pin slides in a bore that is a very close fit and there is hardy any chance of dirt etc. getting to it. It shouldn't really break either but in Rob's case, it somehow had and landed in the trigger assembly, fouling the sears and rendering the trigger very erratic and difficult to set-up. Here is an interesting point ... Inspite of the circlip being missing, I could not get the pin to come out. So how does that work? This is not the first time I have heard this where a rifle seems to work without the circlip. If anyone knows the answer, please let me know.
Hope these pics. and technique will help someone with a similar problem.
Sorry Jain members ... but somehow I dont think Thirthankara Wardhamana Mahavira would work in this context. See below, the circlip next to the end of a biro refil for scale.
Here is a bit of information about it and a way to tackle it that I came across while doing Rob's rifle this weekend.
Where is it and what does it do?
It sits on the Striking Pin (No.40) and holds it in place within the Receiver Body (No.13) - to stop the Striking Pin Spring (No.41) from flying out when the air cylinder is removed. See below.
You can't even see it till you have turned the Body upside down and removed Part Nos. 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71 and 92 out of the way.
Once you have removed them, you need to push the Striking Pin in against the Striking Pin Spring from the front end and look through the slot in the Body provided for housing the trigger assembly.
So how do you work on it?
Well, using a bit of logic I figured out that if I screwed the End Plug, Firing Valve (No.38) back into the Receiver Body, it should push the pin into view. This it did, but not enough to be able to get a grip on it.
So I took some 6mm Dia. bar I had lying around and cut off a length of 5mm. I cleaned this free of burrs and dust, made sure the faces were square to the length and placed it between the end of the Striking Pin and the Firing Valve Gate (No.37) before screwing the Plug into the Body. The power of the Valve Spring (No.35) is clearly way more than that of the Striking Pin Spring and so the pin is pushed and comes more clearly into view allowing you to approach the circlip with a set of slim long nosed pliers. The picture below is heavily enlarged. You can see the groove on the pin where the circlip goes.
When and why would you need to remove this?
Almost never. The Striking Pin slides in a bore that is a very close fit and there is hardy any chance of dirt etc. getting to it. It shouldn't really break either but in Rob's case, it somehow had and landed in the trigger assembly, fouling the sears and rendering the trigger very erratic and difficult to set-up. Here is an interesting point ... Inspite of the circlip being missing, I could not get the pin to come out. So how does that work? This is not the first time I have heard this where a rifle seems to work without the circlip. If anyone knows the answer, please let me know.
Hope these pics. and technique will help someone with a similar problem.