V Mach Twanggggggg

[mturner85 9]

Fitted a v mach to my 95 this morning. She a consistent 11.5 but boy is she twanging it's rattling so much that's it's still rattling 5 mins after the shot lol. Is this normal and just need running in?

[Lancashire Hunter 22]

Did you grease up the spring, piston, spring guide, top hat and piston chamber?

Im no expert but im positive it certainly shouldnt be twangy especialy after a vmack put in.

[mturner85 9]

Yes mate, ive even taken back apart and wiped off all the lube that the v mach comes coated in and reapplied bisley mono. And all other internal parts have been greased. I haven't got a piston sleeve on my 95 though. It's the worst twang and buzz after as well, feels like my gun is going to take off lol. The recoil is worse than before as well. It was relatively smooth before the v mach.

[andyfr1968 772]

Don't put any grease in the 'piston chamber' unless it's a VERY small amount of pure silicon grease. Normal grease will diesel like feck. A light even coating on the spring and guide. A light smear on the top hat if you've got one and the lightest wipe on the piston skirt only.

 

It sounds like something's very not right with your HW, mate. Maybe a piston sleave will help as it sounds like something's way off on tolerence.

[Lewis Ste 245]

How much preload does it have? I fitted one straight into my 97k with the weihrauch spring guide and piston sleeve made from abit of pop can a worked fine and smooth at 11.5. Fitted a new custom spring guide and top hat and it's dropped the power to 10flbs with no piston sleeve and no twang but more preload.

 

I would try a fitting a piston sleeve or top hat to try and remove the spring fore end moving around And make sure the spring guide is a nice snug fit inside the spring but enough clearance to rotate freely. As simple as they are they can be very annoying

[mturner85 9]

Spend spend bloody spend haha. Think I'm going to see if a top hat makes any difference. To be honest how violent it is I can't see it settling. How do you make a sleeve out of a can? Can you sketch me a diagram lol?

[Lewis Ste 245]

You best ask the protuner... The top hat was designed to add weight to the piston and hold the spring in place. (I think) if made from delrin it's only going to weigh a few grams and won't make a diffenerce that way but will stop the spring from jumping round in the piston reducing the twang (his service doesn't offer this product) but the piston liner is just a stainless steel pop can cut into a sheet by chopping the end off then rolling up a sliding into the piston with spring in. Don't have it to tight as the spring will expand slightly when compressed. When just keep taking strips of the end until you have you desired thickness of the sleeve then I rounded of the corners aswel.

That's what I did and worked for me but didn't need it once I had the top hat fitted.

 

By what your saying it sounds like you don't have any preload on your spring so fitting the top hat will compress it abit more aswel

[mturner85 9]

No preload at all. Spring went in easy was a lot shorter than old spring which used to be a pain to put back in.. do you need a can the full length of the piston? Or would like a coke can size do?

[mturner85 9]

Let me get it right. You slide it in the piston or rap it around like a sleeve?

[andy draper 1]

It goes inside the piston mate,same length and diameter,make it a bit longer and cut triangle shapes out of one end,fold these inside it and put this end in the piston first then the spring.The folded under bit is trapped by the spring against the piston head thus holding it in place.You can make them out of a pop can,or get some PTFE sheet off ebay £6 for an A4 size sheet you can get a few from that.In my 97 I made one from 0.5 mm thickness PTFE nice fit but not too tight,any thicker would be too much.

[mturner85 9]

Thanks andy i'm going to try it tomorrow with a can. Also need to order a top hat.

[andy draper 1]

If you are at 11.5 now the top hat will more than likely put you over the limit.Extra weight and greater spring compression plus the liner,as it reduces friction could put a couple of f/p on it.If you have any preload washers fitted I would take them out.