Servicing a 70s Mercury - Spring Choice

[Zomboid]

my advice is don't put a titan spring in it, nowt wrong with the standard bsa springs.With a titan it'll be hard to re-assemble & harsh to shoot + may well be over the power limit unless you cut the spring down & re-fininsh the ends.

You have to cut the spring down. There's absolutely no way a full one will go in and make the rifle nice to shoot. I assembled mine by hand by clamping the trigger assembly unit onto a low lying clamp and then used body weight to compress. Taking 7 coils off was enough to get a decent amount of preload without over doing it and making the firing cycle too harsh.

Nothing wrong with standard springs but the last one I had for my 635 didnt have enough compression on it - no idea why. Came from Chambers who are certainly trustworthy. Went with Titan in the end because I've used them plenty of times without fault - but you do have to shorten them.

[junglie]

You have to cut the spring down. There's absolutely no way a full one will go in and make the rifle nice to shoot. I assembled mine by hand by clamping the trigger assembly unit onto a low lying clamp and then used body weight to compress. Taking 7 coils off was enough to get a decent amount of preload without over doing it and making the firing cycle too harsh.

Nothing wrong with standard springs but the last one I had for my 635 didnt have enough compression on it - no idea why. Came from Chambers who are certainly trustworthy. Went with Titan in the end because I've used them plenty of times without fault - but you do have to shorten them.

Thats your opinion & if you'd read my post properly I did say you'd have to cut a titan down, I find them harsh even cut down correctly prone to buckling & overpriced.apart from a batch in the late 80's to early 90's that were overtempered & prone to break I've never had such problems with the standard bsa merc/airsporter springs & have fitted them to many makes of airgun if they fit correctly. Also not all people have an angle grinder or the skills & knowledge to cut down & compress a coil with a blowlamp & correctly re-grind the ends.

[james_stan]

Thanks for the replies. I have a decent set of tools for general DIY and motorcycle maintenance but I do lack the knowledge! With that
in mind I'll stick with the standard spring etc.. to be going on with - perhaps I'll get adventurous in time. BTW I did take a look at the
Protek web-site but couldn't find a spares section - just me?

Cheers

James

[hotversion]

97 or 77 fits nice

[maximus]

Thanks for the replies. I have a decent set of tools for general DIY and motorcycle maintenance but I do lack the knowledge! With that
in mind I'll stick with the standard spring etc.. to be going on with - perhaps I'll get adventurous in time. BTW I did take a look at the
Protek web-site but couldn't find a spares section - just me?

Cheers

James

Personally I would avoid the Chambers standard spring, they are not BSA ones but obviously sourced by Chambers from another spring manufacturer. They are quite soft and mine lost a lot of length after a small amount of use. I think the HW97 spring mentioned above is a good shout.

[Zomboid]

Thats your opinion & if you'd read my post properly I did say you'd have to cut a titan down, I find them harsh even cut down correctly prone to bucking & overpriced.apart from a batch in the late 80's to early 90's that were overtempered & prone to break I've never had such problems with the standard bsa merc/airsporter springs & have fitted them to many makes of airgun if they fit correctly. Also not all people have an angle grinder or the skills & knowledge to cut down & compress a coil with a blowlamp & correctly re-grind the ends.

I re-read it - post implied not to fit one at all and only mentioned the shortening at the end - hence my wording. Just a miscommunication on both sides I think.

Odd you mention the mistemperings. I recall having that exact experience around then when I was destroying/tuning a Meteor (I was young and stupid). Had a couple of springs which did exactly that. All my decent tunes have been in the last 5-6 years with BSAs and HWs. Depends how you like your set up I guess and what you do with it.


TO THE OP: Plenty of you tube vids on how to do some of the more technical stuff. Shortening springs is actually one of the easier things and you can of course practice on the old spring too.

[ZAKDINGEL]

Cant believe no one has suggested using a mighty OX spring these were the best available back in the day -----Or the only one the shops had left