TX200 piston extension

[sherlock1963]

Does anyone on here have or make a TX200/PS piston nose that takes the Air Arms piston seal?

I know the HW/LGU seals are more efficient but I wanted the AA one for an experiment.

Thanks.

[DESERT FOX]

I enquired about one as you describe with Tinbum tuning.
Nick told me that machined to take the AA seal it would cause a big weak spot in the extension.

[sherlock1963]

Thats a shame. They were the original short-stroke drop-in design before the HW seal conversion. I will look in another direction.

[hmangphilly]

Thats a shame. They were the original short-stroke drop-in design before the HW seal conversion. I will look in another direction.

how much do you want to extend your piston by ?

[sherlock1963]

how much do you want to extend your piston by ?

Its for a Pro Elite, sleeved to 25mm. A MK1 TX piston is 25mm too short.
I am hoping to get an extended piston rod. I wanted to try different stroke lengths.
A 25 or 30mm extension TX to HW seal would do but nobody makes them.

[Shed tuner]

Its for a Pro Elite, sleeved to 25mm. A MK1 TX piston is 25mm too short.
I am hoping to get an extended piston rod. I wanted to try different stroke lengths.
A 25 or 30mm extension TX to HW seal would do but nobody makes them.

lol.... you should have said so. Make it in ally - loads of material to machine to take whatever seal you like.
BTW An LGV piston will be much closer, as they are longer, so you will lose less spring room. I had a complete new custom (longer) piston made up - much better solution.

remember my old Pro Elite sleeving thread ? i used 20mm extension, but an AA seal is 5mm slimmer than an HW seal, so your 25mm is bang on... But as you need to lose stroke anyways (to clear the rear piston shoulder), why not just use the far superior LGV/U/HW seals ?

[sherlock1963]

lol.... you should have said so. Make it in ally - loads of material to machine to take whatever seal you like.
BTW An LGV piston will be much closer, as they are longer, so you will lose less spring room. I had a complete new custom (longer) piston made up - much better solution.

remember my old Pro Elite sleeving thread ? i used 20mm extension, but an AA seal is 5mm slimmer than an HW seal, so your 25mm is bang on... But as you need to lose stroke anyways (to clear the rear piston shoulder), why not just use the far superior LGV/U/HW seals ?

The problem is I have no engineering skills, only ideas. So I need a skilled lathesman (is that a word?) to take my money in exchange for their work. I have an LGU piston but Tinbum doesn't do piston noses for them so I thought I might try another route.

I have read and enjoyed your various PE threads and would like to proceed but I'm stuck without a suitable piston.

[tinbum]

The problem is I have no engineering skills, only ideas. So I need a skilled lathesman (is that a word?) to take my money in exchange for their work. I have an LGU piston but Tinbum doesn't do piston noses for them so I thought I might try another route.

I have read and enjoyed your various PE threads and would like to proceed but I'm stuck without a suitable piston.

Yet!! I need a piston/gun to play with. Hopefully I'll find one at the binfire bash.🙂

[sherlock1963]

Yet!! I need a piston/gun to play with. Hopefully I'll find one at the binfire bash.🙂

I can send you a piston

[Shed tuner]

The problem is I have no engineering skills, only ideas. So I need a skilled lathesman (is that a word?) to take my money in exchange for their work. I have an LGU piston but Tinbum doesn't do piston noses for them so I thought I might try another route.

I have read and enjoyed your various PE threads and would like to proceed but I'm stuck without a suitable piston.

Tell Tinbum the LGU piston nose is exactly the same as an HW piston nose, than may simplify things
That piston is what, around 15mm longer in the body than a TX one ?

[sherlock1963]

Tell Tinbum the LGU piston nose is exactly the same as an HW piston nose, than may simplify things
That piston is what, around 15mm longer in the body than a TX one ?

The LGU piston is 11mm longer than a MK1 TX, that includes the 5mm extra length of the LGU piston seal compared to AA.

I reckon a 15mm extension on the LGU piston gives a 90mm stroke in a PE. As a guess 20mm would be better. The transfer port of my PE is 3.45mm (not sure of the length, do you know Jon?)

[Shed tuner]

The LGU piston is 11mm longer than a MK1 TX, that includes the 5mm extra length of the LGU piston seal compared to AA.

I reckon a 15mm extension on the LGU piston gives a 90mm stroke in a PE. As a guess 20mm would be better. The transfer port of my PE is 3.45mm (not sure of the length, do you know Jon?)

TP info also here http://www.airgunbbs.com/showthread....-m-building-it

tp is around 12mm long. Your port is larger dia than mine - mine was 3.0. Either they changed the design, or someone has opened yours out. I actually opened mine out to 3.2, so it's not so different. 3.45 would be better for FAC / longer strokes.

Whatever stroke you want to run, just make 100% it clears the cocking shoe at the end of the cycle... 80mm works well, 90mm is a bit excessive IMHO.

[sherlock1963]

TP info also here http://www.airgunbbs.com/showthread....-m-building-it

tp is around 12mm long. Your port is larger dia than mine - mine was 3.0. Either they changed the design, or someone has opened yours out. I actually opened mine out to 3.2, so it's not so different. 3.45 would be better for FAC / longer strokes.

Whatever stroke you want to run, just make 100% it clears the cocking shoe at the end of the cycle... 80mm works well, 90mm is a bit excessive IMHO.

I did wonder if the TP was larger than standard. It's one of the later rifles (2002) but I suspect a previous owner is more likely to be the culprit. I was hoping for low 80s stroke as my TXs shoot well at that (and shorter)

As and when I can source the parts needed I will post some updates

Thanks for the info and help Jon.