Anschutz 335 mk1/2 ptfe washer

[weebster]

Thought I would post this here as well as it might be of some use to people....

I have had a chance to have a play with the ptfe washer from TR ROBB in both the mk1 335 and mk2 335,although I will state now that I did not re-size the ptfe washer for the mk1 but instead ran that test straight out of the packet so to speak,the reason being I did the mk1 first as it was already stripped in prep for a synthetic seal off fleabay and I have found the mk1 has a slightly tighter chamber than the mk2.Whether that is down to the often spoke about 'bulge' or down to the mk1 having seen very little use I have no idea....could just be one of those things that happen in large scale manufacturing.
Anyway as previously mentioned these two 335's have different springs and the specc is set out below.
Both rifles have had the piston polished,a light buffing of the chamber with solvol autosol,piston lined with ptfe sheet and a 2.2mm nylon washer at the spring guide end.

Firstly the mk1 I know will do 10 ftlbs with a vortek seal and just under 10 ftlbs with the seal of fleabay ,with original washer it is doing 7.5 ftlbs.
I fitted the ptfe washer with no sanding down,as suspected it was a tight fit and only returned 6 ftlbs but I suspect by sanding down to a nice easy fit it would improve.

The mk2 was doing 9.89 ftlbs with the vortek seal and only 7 ftlbs with the original leather washer,now before fitting the ptfe washer it was re-sized as per instructions while on the piston until it was a nice easy fit,I then put around 50 shots through it into the ground to bed the washer in then over the chrono for a few shots...the result was 589 fps for 11.17 ftlbs using rws superdome 14.5 grn pellets.

I will at some point in the next few days put plenty shots down range then chrono again to see how it settles and if all goes well I will buy another for the mk1 but re-size it to fit......spring specs below.
Measurements are as close as I could get but did vary a little up and down the length of springs.

Mk 1
length // 242mm
wire // 3.03
od // 20.62
id // 14.48


Mk 2
length // 215mm
wire // 3.42
od // 21.46
id // 14.60

[andrewM]

A most interesting experiment that seems to have paid off. Not being mechanically minded, I would have kept the original leather washer. It seems, however, the new washer has worked.

I wonder how you will find the accuracy at a range test.

Subject the above, it begs the question as to whether other old rifles should be fitted with new washers to improve power. I cannot believe it would be as simple as this but perhaps we will begin a discussion here.

Rgds
Andrew.

[clarky]

Thought I would post this here as well as it might be of some use to people....

I have had a chance to have a play with the ptfe washer from TR ROBB in both the mk1 335 and mk2 335,although I will state now that I did not re-size the ptfe washer for the mk1 but instead ran that test straight out of the packet so to speak,the reason being I did the mk1 first as it was already stripped in prep for a synthetic seal off fleabay and I have found the mk1 has a slightly tighter chamber than the mk2.Whether that is down to the often spoke about 'bulge' or down to the mk1 having seen very little use I have no idea....could just be one of those things that happen in large scale manufacturing.
Anyway as previously mentioned these two 335's have different springs and the specc is set out below.
Both rifles have had the piston polished,a light buffing of the chamber with solvol autosol,piston lined with ptfe sheet and a 2.2mm nylon washer at the spring guide end.

Firstly the mk1 I know will do 10 ftlbs with a vortek seal and just under 10 ftlbs with the seal of fleabay ,with original washer it is doing 7.5 ftlbs.
I fitted the ptfe washer with no sanding down,as suspected it was a tight fit and only returned 6 ftlbs but I suspect by sanding down to a nice easy fit it would improve.

The mk2 was doing 9.89 ftlbs with the vortek seal and only 7 ftlbs with the original leather washer,now before fitting the ptfe washer it was re-sized as per instructions while on the piston until it was a nice easy fit,I then put around 50 shots through it into the ground to bed the washer in then over the chrono for a few shots...the result was 589 fps for 11.17 ftlbs using rws superdome 14.5 grn pellets.

I will at some point in the next few days put plenty shots down range then chrono again to see how it settles and if all goes well I will buy another for the mk1 but re-size it to fit......spring specs below.
Measurements are as close as I could get but did vary a little up and down the length of springs.

Mk 1
length // 242mm
wire // 3.03
od // 20.62
id // 14.48


Mk 2
length // 215mm
wire // 3.42
od // 21.46
id // 14.60

The key with the 335 is actually retaining the original washer. They are still available if you shop around.
The PTFE job from TR is terribly temperature sensitive and high figures can be expected in this cold snap we are having.
The leather is virtually immune to temp variations but slow at 10.1 ftlbs or so.
Whats needed is a stroke adjustment. Very easy to do on a lathe. The 335 is a Feinwerkbau Sport trying to get out but with a better trigger.
A very underrated gun and that just disappeared with the arrival of Fwb sport

[billsnibby]

Hi,

apologies for any thread hijacking, but I'm very interested to know the details of the simple modifications to lengthen the stroke of a 335?

Best Regards,
Bill.

[weebster]

The key with the 335 is actually retaining the original washer. They are still available if you shop around.
The PTFE job from TR is terribly temperature sensitive and high figures can be expected in this cold snap we are having.
The leather is virtually immune to temp variations but slow at 10.1 ftlbs or so.
Whats needed is a stroke adjustment. Very easy to do on a lathe. The 335 is a Feinwerkbau Sport trying to get out but with a better trigger.
A very underrated gun and that just disappeared with the arrival of Fwb sport

I must admit I have never used a rifle fitted with a ptfe washer before so am unaware of temperature having a negative/positive effect,are you saying come high summer temps the ptfe washer will bind causing a drop in power?
Problem I find with leather is getting it 'friction' free...ish,obviously both these rifles are capable of hitting 10ft lbs with just a more modern washer,so why is it they are not doing so with the leather washers,both of which look fine condition wise.
Isn't the webley omega a rifle that has the ptfe washer?

[clarky]

I must admit I have never used a rifle fitted with a ptfe washer before so am unaware of temperature having a negative/positive effect,are you saying come high summer temps the ptfe washer will bind causing a drop in power?
Problem I find with leather is getting it 'friction' free...ish,obviously both these rifles are capable of hitting 10ft lbs with just a more modern washer,so why is it they are not doing so with the leather washers,both of which look fine condition wise.
Isn't the webley omega a rifle that has the ptfe washer?

The problem with PTFE is despite its lowest known coefficient of friction it nontheless is affected by temperature changes and will have a tendency to spread in dia on occasional diesels.
An accidental dry fire can send it rock tight.
Vortex do an O ring fitted into a neoprene washer which works v well but leather washers can work superbly using neatsfoot oil as a light but regular maintenance .....avail from John KNibbs..

[clarky]

Hi,

apologies for any thread hijacking, but I'm very interested to know the details of the simple modifications to lengthen the stroke of a 335?

Best Regards,
Bill.

The balance parameters of the 335 is that it was spoiled somewhat by its transfer port being too big for the ratio of stroke reducing its power similar to the Webley mk3 .....it really needs to be about 2.8mm
The head is screwed into a front wall which is not too hard to skim with a tip tool by a approx 2mm adding greater volume.
Restricting the transfer port would be more effective and efficient but a skilled job.
Like i said a FWB trying to get out ....ive known some outshoot sports with 335s.
Bowkett did a transfer port modded version at 11.4 ftlbs one time