HW piston seal for TX200 MK3 conversion Is it 25 or 26MM

[10/10]

Info Reqd
I have just acquired a TX200 MK3 HC, i have not stripped yet but i will want to fit a Weihrauch type piston seal
so do i require a 25 or 26mm seal ?

[hmangphilly]

Tx is 25mm Mr.10

[robs5230]

You'll need an extension to the piston to run a HW seal in a TX, thereby short stroking it.
Check out tinbum tuning website. http://www..com/product/air-arms-tx2...ort-pro-kit-2/

Personally I'd stick with the factory seal and the mk3 stroke.

[10/10]

This seems a bit of a minefield. A lot of different way to go on this one
I have already spoken to others on this subject but all imformatiom welcome

[robs5230]

This seems a bit of a minefield. A lot of different way to go on this one
I have already spoken to others on this subject but all imformatiom welcome

I'd recommend shooting a short stroked one before changing yours. The cycle of a short stroked one is a fair bit snappier as it needs more spring power to compensate for the shorter stroke.
However it ends up, the tx is a fine rifle.
If its not been apart before and in standard trim, a basic delrin drop in kit will make a massive difference

[32:1]

Ive not long had my tx and got the hw extension and a vortek to replace the original if the SS didnt suit me.

Well, I couldnt tell that much difference between all three setups, although the ss kit only latches once, I couldnt say if it was much harder to cock either. But the rifle has been left with my preffered setup which is the tbt guides and the vortec seal, as this needed the spring trimming as it went over, it feels nice (to me)

There was one thing I kept thinking about and it became a worry, those little screws holding the SS head on ? I did locktite and it was probably going to shoot 1000's of times with no hassle but it just niggled me, so that and a softer shot cycle with the vortec made my mind up

Chris

[10/10]

I was thinking of getting the end of piston ( into the latchrod drilled and tapped with the appropriate spacer)

[Shed tuner]

Personally I'd stick with the factory seal and the mk3 stroke.

Each to their own, but besides cocking effort, I don't know anyone no-one who has actually shot a properly configured stroke reduced Mk3 who doesn't prefer it to the long, lazy, hold sensitive cycle of the factory gun...

There is no such thing as "a" short stroke BTW - you stroke can be set anywhere you like.. from as short as 77mm to as long a 98mm factory. Optimum depends on calibre, barrel length, piston weight, and personal preference. If you use a nose threaded onto the latch rod, you can tune to your liking. If you like it soft, I'd go for 88mm, same as an LGU. personally I've settled on around 83 (same as a factory mk1/2 - so can you even call this "short stroke" ? ), with a reduced TP and reduced piston weight.

[Shed tuner]

I was thinking of getting the end of piston ( into the latchrod drilled and tapped with the appropriate spacer)

the best method is to remove the piston latchrod (heat it up, it's loctited, and unscrew
face off the piston - removing the AA seal dovetail
reduce the piston weight by trimming a mill off the contral section of the body, and throw the steel TH away - should get it down to 200g ish easy
machine a new ally nose adapter / spacer for to take the HW seal
bore and thread the adapter M10 - the same as the latch rod
thread the latch rod back through the piston and into the adapter.
optimal setup involves the above, but reducing the size of the nose adapter/spacer and buying a new longer latch rod - this gives you more spring room, and a nicer short cycle.

However, I would suggest you shoot a (properly done) short stroke gun first. Simply slapping a nose extension on is OK, but it can be a bit slammy with the std piston weight and TP. Worse if you leave the steel TH in.

If you can make it to Mick's springer bash, you can try before you take the plunge.

[10/10]

Now the above sounds interesting and would be a simple job for my engineer

[10/10]

Out of curiosity why not make the nose cone adapter out of nylon 66 ?
P.S When and where is the next springer bash

[robs5230]

Each to their own, but besides cocking effort, I don't know anyone no-one who has actually shot a properly configured stroke reduced Mk3 who doesn't prefer it to the long, lazy, hold sensitive cycle of the factory gun...

There is no such thing as "a" short stroke BTW - you stroke can be set anywhere you like.. from as short as 77mm to as long a 98mm factory. Optimum depends on calibre, barrel length, piston weight, and personal preference. If you use a nose threaded onto the latch rod, you can tune to your liking. If you like it soft, I'd go for 88mm, same as an LGU. personally I've settled on around 83 (same as a factory mk1/2 - so can you even call this "short stroke" ? ), with a reduced TP and reduced piston weight.

I was assuming he'd go for an extension and a HW seal. Turns out he's not planning that.
When saying short stroke I just meant shorter than the mk3.

As for the long lazy hold sensitive mk3 cycle, thats subjective too. Mine was none of those. Far from standard but definitely standard stroke. It would outshoot my PCP from a bench and shot as well offhand. Took many rabbits. The only reason I got rid was the weight. It actually shot better than a .22 mk2 spec one that I owned at the same time.
Horses for courses though, my way is just that, my way.

[FPoole]

The new latch rod is best, but the HW seal ,IMO, just isn't a necessity. I've just taken a lightened LGU piston, with the HW type seal and short stroke, out of one of my MarkI guns. I replaced it with the factory piston and a Maccari Apex seal and I just can't feel any difference in the two. I gained a couple of mm's stroke, so I think that made up for any "lost volume" the factory seal may have. I don't chrono as a rule(no power limit here), but this set up takes about 4 (1/8th) clicks less elevation at 55 yards so the power is very close to the same. If you go new latch rod, and milling off the dovetail for the HW adapter isn't a problem, I see no reason not to try the HW seal as well. I just didn't feel a difference, even though the HW seal may be more efficient.

[cooper_dan]

Genuine question. Is the hassle of going to a hw seal worth it? Or would it better to keep the AA seal and have the extra spring room?

My tx is 80mm stroke (with new latch rod), standard mk2 spring and standard AA seal. Zero power washers gives 10.8 ft-lb and a really nice (to me) shot cycle.

It's already been said but try other people's mods first if you can. I know people who have bought every tuning kit going but none suited them because they didn't actually know what they wanted

[clarky]

Out of curiosity why not make the nose cone adapter out of nylon 66 ?
P.S When and where is the next springer bash

...because its a shocking material...if you glass the machine work with anything more than a pair of specs, it looks like a raggy ploughed field, regardless of negative rake tip tools, sharp full rake etc...its just darn difficult to finish and its temperature coeffic is poor...
Delrin or Aircraft grade alloy much better all round.
I think 66 or the self lubricating graphited variants have had their day.