Long Stroke piston comp tube HW77

[electric sheepy]

I have spoken to V mach about making up a long stroke kit but it will take time, if anyone has the skills I would appreciate a quote. I need 9mm to get the 11fpe from the super soft set up I want. I know short stroke is the fashion but I have long enjoyed the HW80 modified for minimal spring. I have been away for some time but weathered the storm and made it back to the BBS tent, I do not want to replicate my old posts about spring gun tuning my way because it is just the way I like it not the way I believe others should or should not

[mrto]

Sorry I can't help you,but it's refreshing to see someone talking about long stroking for a change.

[electric sheepy]

If I want snap I shoot my rimmy, recoil CF and for a shove BP (rare now as I let my Grandfathers blunderbuss go for too little money and much regret) but with air I love the unstressed bellows of a gun rather than the coiled high tension of short strokes. It pays dividends with accuracy for me and is consistent. My old 77 with longstroke had fps variation that could be down to pellet weight alone (well almost) The action is very quiet and low vibration, easy on optics. Perhaps longer pulse of the stroke dissipates the energy lost to the system and not the pellet in a way that just feels and sounds right, much the way things just look right. Not an empirical analysis but subjective and my own. The HW80 is my gun of choice but having sold the best I owned or fettled I cannot yet bring myself to take another

[bigtoe01]

Do it yourself, it just involves shortening the latch rod from the nose end 5mm for 5mm more stroke, then dry building the gun to see if the skirt clears the trigger block ok...if it does not drop it in a machine shop and have them take a few mm off the skirt till it clears. The way to do this is to get a dremel and grid off the case hardening for 2mm from the end of the skirt so it can then be lathed off..or just use super hard cutting bits and loads of fluid

When i say dry build, all you do is install the trigger into the bare trigger block then push the piston into the trigger so to cock /latch it...i do this pushing against the work bench..dead easy, this way you can see if any piston skirt needs to come off.

Then have a look at the comp tube on a full dry build...see if this will clear the trigger block...if it doesn't then shorten in lathe

Last cocking linkage and under lever...again on the dry build so you can make sure everything clears.

Or...ask Wonky to have a look, it would make his day to long stroke over a short stroke LOL, although his short strokes will imo out shoot a long stroke all day

[electric sheepy]

Getting the latch rod out is tough, very tough and having given up shooting once I also gave up tooling.

[TonyL]

Out of interest, Sheepy, what specification of spring were you using in the soft 80?

Longer, with thinner wire, smaller OD and thicker piston sleeve, or shorter, stiffer spring?

[p.j.]

I have a long stroke HW77 (8mm extra), which was done by Venom. The process is as outlined by bigtoe, some wood needs to be removed from the stock to accomodate the extra swing on the underlever, and a little bit of filing on the underlever pivot point. Mine is a FAC conversion, making 17ftlb.

[bigtoe01]

Its not hard to get the latch rod out of a HW piston, even when the cross pin is a blind fit...just drill 180deg to the pin till you hit it, then drift it out from the hole you just drilled..then its easy to tap the latch rod out to do some work on it. The 25mm piston cross pins are not blind...so its even easier.

[TheWilding]

I long stroked my Diana Model24D, similar to as BT described it..... I cut the skirt off using a stainless steel cutter in a 4.5inch grinder with the piston chucked up in a drill. I then machined the new latch indent into the latch rod with it still in the piston, I had to make up some support blocks to hold the piston and use a drill to spin it, to do the machining I again used either the stainless cutter and dremmel to finish/polish it. I then heated it up and re hardened it.

This is on a TO1 trigger, with 3 retaining balls, over all I gained 16mm of swept volume, I had to cut around 4 coils off the standard spring to get it back down below 6fpe, especially after the TP work I also did, shoots really nice now


ATB

Sean

[Barryg]

I have spoken to V mach about making up a long stroke kit but it will take time, if anyone has the skills I would appreciate a quote. I need 9mm to get the 11fpe from the super soft set up I want. I know short stroke is the fashion but I have long enjoyed the HW80 modified for minimal spring. I have been away for some time but weathered the storm and made it back to the BBS tent, I do not want to replicate my old posts about spring gun tuning my way because it is just the way I like it not the way I believe others should or should not

Excellent idea to long stroke the 77 there will be a less strain on the suspect cocking link that would wear quicker with a short stroke.

As you say short stroke is the fashion but I am still one of the minority long stroke fans left on the bbs

[Shed tuner]

Or just buy a TX200 MK3

[T 20]

Excellent idea to long stroke the 77 there will be a less strain on the suspect cocking link that would wear quicker with a short stroke.

Hi Barry

I tried Googling "cocking lever break" and just came up with loads of hits like this one :-

http://www.network54.com/Forum/18447...60+cocking+arm








All the best Mick

[Barryg]

Hi Barry

I tried Googling "cocking lever break" and just came up with loads of hits like this one :-

http://www.network54.com/Forum/18447...60+cocking+arm







All the best Mick

Hi Mick, I think that you have misunderstood the part that I mean
Its the cocking link that I mean not the lever.
It might not wear and drop out if long stroked as less strain on that area in the pic below.

http://i900.photobucket.com/albums/a...psd499305c.jpg

[T 20]

Hi Mick, I think that you have misunderstood the part that I mean

No misunderstanding Barry

The HW 77 has been in continuous production for the last 31 years with hundreds of thousands of guns sold, and as far as I know there are only two documented incidents of the cocking lever foot breaking due to use.

So hardly worth mentioning compared to the cocking arm problem on the Diana 460 which I'd class as being a poor design using inadequate materials.




All the best Mick

[Barryg]

No misunderstanding Barry

The HW 77 has been in continuous production for the last 31 years with hundreds of thousands of guns sold, and as far as I know there are only two documented incidents of the cocking lever foot breaking due to use.

So hardly worth mentioning compared to the cocking arm problem on the Diana 460 which I'd class as being a poor design using inadequate materials.

All the best Mick

Mick first let me explain about the 460 as you mention it, when the 460 was first out Diana was fitting some mod 300r parts that would have been adequate if shooters in the USA would have kept to about the same power as the 52 but you know what it is they over cranked them and the old 300r lever was not made for heavy cocking effort so was breaking, so diana responded and have updated (look at the pics) but just like the side lever if you go over 50 lbs cocking effort there is a risk that the levers on both the 460 and 52 might crack, 36 lbs cocking effort is about the correct cocking effort for the usa.
You can see what I mean in these pics
http://i900.photobucket.com/albums/a...ps63f6ea4f.jpg

http://i900.photobucket.com/albums/a...psb1fee482.jpg

But I am not sure what you mean when you say about the 77/97 not having a weakness with the cocking link, why would airgun world mention it in a article all those years ago if there are only two documented incidents