HW35 With Rotating Piston

[T 20]

Have you considered a piston without bearing by the piston seal?

As with many break barrel guns, when you cock an HW35 the tail of the piston is pushed upwards and the nose of the piston tends to be forced downwards, so the use of a front bearing keeps the piston parallel in the cylinder.




All the best Mick

[Bruno27]

As with many break barrel guns, when you cock an HW35 the tail of the piston is pushed upwards and the nose of the piston tends to be forced downwards, so the use of a front bearing keeps the piston parallel in the cylinder.
All the best Mick

Agree Mick. As you cock the rifle, most of the load is taken by the rear bearing surface. I consider the load at the front of the piston to be negligible during cocking, the seal being able to take this load and as you fire the gun, the only force is on the axis of the piston (if you ignore moment on this axis induced by the spring). I have modified the piston of my Diana 35 (old) with no front bearing and it works fine.

Less friction = more power and more consistency

Cheers, Bruno

[T 20]

Agree Mick. As you cock the rifle, most of the load is taken by the rear bearing surface. I consider the load at the front of the piston to be negligible during cocking, the seal being able to take this load and as you fire the gun, the only force is on the axis of the piston (if you ignore moment on this axis induced by the spring). I have modified the piston of my Diana 35 (old) with no front bearing and it works fine.

Less friction = more power and more consistency

Cheers, Bruno

Hi Bruno

Thinking about it, the Diana 35 and many other Diana break barrels would be ideal to convert to rotating Pistons due to their sear rod and trigger arrangements.



I'm on my last rusting of the HW35 cylinder before it gets dunked in Kerosene for 24 hours to harden off, so hopefully I'll have this 35 up and running by next weekend.

[TonyL]

Be great to hear what it's like once together, Mick.

[Shed tuner]

I'm on my last rusting of the HW35 cylinder before it gets dunked in Kerosene for 24 hours to harden off, so hopefully I'll have this 35 up and running by next weekend.

slightly more rapid progress than your "improved" airsporter then

[T 20]

slightly more rapid progress than your "improved" airsporter then

Ah well Jon, my life got put on hold when I collapsed on August bank holiday last year and had to spend six months lying down.

I'm still not right but I'm trying to get a few projects sorted, top job on the list is sorting my fume bluing setup --- but I think I've about cracked it now thanks to B&Q.

A B&Q immersion heater element in one of their 90cm long planters makes an excellent electric boiling tank, and a second 90cm long plant pot with lid makes a good rusting tank.




All the best Mick

[joffy]

Agree Mick. As you cock the rifle, most of the load is taken by the rear bearing surface. I consider the load at the front of the piston to be negligible during cocking, the seal being able to take this load and as you fire the gun, the only force is on the axis of the piston (if you ignore moment on this axis induced by the spring). I have modified the piston of my Diana 35 (old) with no front bearing and it works fine.

Less friction = more power and more consistency

Cheers, Bruno

The guide also helps keep the piston flying straight and true as the latch rod is inside it all the time