I must have the weakest HW80 in the UK

[Barryg]

It's a bit odd as its still running really nice but it was doing about 10.5 ft/lbs but checked it today and now about 8.3 ft/lbs, when I dismantled it, it all looks fine, seals etc.

I guess it's a new spring needed but it doesn't feel weak and the spring is only 20 years old

Any ideas?

[robs5230]

It's a bit odd as its still running really nice but it was doing about 10.5 ft/lbs but checked it today and now about 8.3 ft/lbs, when I dismantled it, it all looks fine, seals etc.

I guess it's a new spring needed but it doesn't feel weak and the spring is only 20 years old

Any ideas?

That guide looks bone dry and far more preload than I'd want.
But as you say, I'd suspect the spring

I'd start with a spring the same spec but at least a coil longer, and ditch 2 of those preload washers. Go from there.

[Barryg]

That guide looks bone dry and far more preload than I'd want.
But as you say, I'd suspect the spring

I'd start with a spring the same spec but at least a coil longer, and ditch 2 of those preload washers. Go from there.

When installed plenty of moly it has 29 coils but it is a soft spring, I suppose it's just fatigued, it's a shame as I have always had no problems with power like most springs in an 80.

[madcarlos]

I had similar in my old hw77, I had put new kit in a couple of years back but hardly used it , Shot it one day and it sounded a little funny, Noticeable enough to know it was not right, As everything was newish or at least had not been used much my thoughts were with the breech seal, Unfortunately i bought new spring which was longer than the one from the kit and guess what, Exactly the same . Bought then a new breech and piston seal and out of curiosity I popped the old breech seal out and fitted the new one, Yes it was the bloody breech seal , Quite noticeably thinner thaf the new one to, I have another 77 and a 97 so the spring wont go waste , Thing was the breech seal was a gut feeling which turned out to be right.

[TonyL]

I'd put it down to that effete looking pinky / purply piston sleeve, Barry..

[TonyL]

But as you say, I'd suspect the spring

I'd start with a spring the same spec but at least a coil longer, and ditch 2 of those preload washers. Go from there.

Yep, would agree. And, as above also, pop a new breech seal in there.

[Barryg]

Yep, would agree. And, as above also, pop a new breech seal in there.

I have stuck with this spring for so long because it would never go over the limit, I have tried quite a few springs over the years including Titan and F1 and it didn't matter how many coils I cut of it just wanted to go and soft springs are not easy to get (are they)

[TonyL]

I have stuck with this spring for so long because it would never go over the limit, I have tried quite a few springs over the years including Titan and F1 and it didn't matter how many coils I cut of it just wanted to go and soft springs are not easy to get (are they)

I can understand why you've kept this spring in for so long for fear of it straying over, Barry, as, as stated, it's so easy for an '80 to cross over into NaughtyLand.

If you were going to replace, a good place to start to get an idea might be the Mainspring Data Thread. I'd be thinking along the lines of a TX, 77, 95 or a thinner wired Titan coupled with custom guides and thicker piston sleeve, methinks.

[maximus]

How tight is the seal in the cylinder Barry? You look to have a few washers on the guide to up the pre-load already, where does the guide come relative to the end of the cylinder with the back block removed? Like you say a soft spring is difficult to come by these days. Although the original springs are thick wire they are large diameter with a short pitch and can be quite soft compared to some of the after market ones. Its not easy to get a genuine HW replacement but thats what I would do or you will have to have new guides.

[where's it gone]

Best way to test a break barrel breech seal is to put a dusting of talcum powder over the join. Saves dismantling.

[Barryg]

How tight is the seal in the cylinder Barry? You look to have a few washers on the guide to up the pre-load already, where does the guide come relative to the end of the cylinder with the back block removed? Like you say a soft spring is difficult to come by these days. Although the original springs are thick wire they are large diameter with a short pitch and can be quite soft compared to some of the after market ones. Its not easy to get a genuine HW replacement but thats what I would door you will have to have new guides.

Hi Max, it's a simple setup soft spring, Tinbum guide/top hat and my own strong plastic sleeve, new breech seal and a nicely run in piston seal so a mystery that it has lost two FP

[angrybear]

Could it be a chrono fault, Had the POI dropped ?

[Shed tuner]

Could it be a chrono fault, Had the POI dropped ?

or a pellet weight fault...

[Murphy]

I bought a SH under 12 month old HW80k and it was only doing 7.9ftlbs from memory.

The previous owner had no idea it was shooting so low.

The only thing different I could see inside was a cut spring with a grinder like what come from HC.

[Barryg]

Could it be a chrono fault, Had the POI dropped ?

I'll check it later just in case but I still think it's the spring fatigued.