Steel tubing

[joffy]

ahhh.... what piston are you using ?

It's a TX piston with the mk1 rod

[Shed tuner]

It's a TX piston with the mk1 rod

I think that rod will be a way too short - have you mocked it up to check ?
Also I think the piston itself will be too short as well - you'll need a nose extension - the problem IIRC from mine (it was a while ago) was when the piston is on the forwards position, the rear shoulder would have smacked into the cocking shoe. Hence the need to lengthen.
Assume you are using the new style "in the groove" cocking shoe ? Any you know about grinding the HW sear if you want a rotating piston ?

Its a worthwhile project though, you'll end up with a loverly gun.

[joffy]

I think that rod will be a way too short - have you mocked it up to check ?
Also I think the piston itself will be too short as well - you'll need a nose extension - the problem IIRC from mine (it was a while ago) was when the piston is on the forwards position, the rear shoulder would have smacked into the cocking shoe. Hence the need to lengthen.
Assume you are using the new style "in the groove" cocking shoe ? Any you know about grinding the HW sear if you want a rotating piston ?

Its a worthwhile project though, you'll end up with a loverly gun.

Got the piston from mick (t20) at the last bash minus the rod which I just had made.....i had been looking at one of nicks shortstroke extensions with the hw seal.... The 80 already has the new shoe fitted

[joffy]

The 80 is running a short stroked/lightened standard piston....i can pick up some 30mm od 24mm id so might get the gunsmith I use to take it out a touch to 25mm

[T 20]

Got the piston from mick (t20) at the last bash minus the rod which I just had made.....i had been looking at one of nicks shortstroke extensions with the hw seal.... The 80 already has the new shoe fitted

Bloody hell Jonathan, I bought one of those extensions off Neil54 at the last bash, I only bought it for the 25mm Weihrauch seal --- you can have the extension.

I'd have gone with the Walther LGV piston in an 80 --- Bigtoe (Tony Leach) shows how simple the conversion is with one of those on his old Airguntech website.

All the best Mick

[Shed tuner]

yeah, TX piston will work with a nose extension and a new longer rod - but as Mick says, the Walther piston might be the better bet, as the nose extension just wastes spring room...

[joffy]

Now I have a spare piston for my mk1

[Neil54]

Cold Drawn Seamless mechanical tube.
25.4 ID wall = 2.34
+/- 0.08

[joffy]

Anyone got an lgv piston

[joffy]

Cold Drawn Seamless mechanical tube.
25.4 ID wall = 2.34
+/- 0.08

Finding an offcut or just half a metre is looking rather elusive

[T 20]

Now I have a spare piston for my mk1

image.jpg

[joffy]

image.jpg

Cheers mick just spent the last half an hour trying to order using my phone 30 secs on the pc

[T 20]

I've just realised this afternoon, you could use a machined down TX compression tube to sleeve the compression chamber down to 25mm.

[Shed tuner]

I've just realised this afternoon, you could use a machined down TX compression tube to sleeve the compression chamber down to 25mm.

trouble is, they are a b'stard to machine.... very hard.. not sure what they are made of, but I gave up on that idea very quickly...

[joffy]

trouble is, they are a b'stard to machine.... very hard.. not sure what they are made of, but I gave up on that idea very quickly...

Just as well... I didn't buy one