Quote Originally Posted by TonyL View Post
At 11.8 FT.lbs, Darren, it's a bit too close for comfort.

What pellets are you using?

If you were using 8.44 gr pellets, just 7 feet per second will have you at 12.0.

Now, you can make the '80 much sweeter, depending on how far you want to go.

The '80, at 30mm bore, has a pretty hefty piston. If you reduced piston weight that would help. And if you were to reduce the stroke, that would also help.

However, if you generally like it the way it is, and just want to make it a little more refined, I'd be stripping it. Degrease, de-burr and polish. Fit a top hat. If the standard guide is a snug fit on the spring, you could stick with that. If not, an aftermarket guide that fits your spring nicely will help quieten things down. If there's room and if there isn't one already fitted, a piston sleeve will also help towards refining the firing cycle.

Then I'd be removing or collapsing a coil from the spring to get the power down. If keeping the piston weight and stroke standard, this may make the firing cycle feel a little lazier. But many prefer them like that anyway and the result will be a more refined shooting rifle that's safely below the limit.

Hi Tony -- yep I get your drift , using AA field 8.44 , strange 2 separate tins of same pellets gave different fps , one tin was about 5 yrs old and faster by 20fps , putting it even higher , but the second tin a new unopened tin of same pellet kept it at 11.8 level , both ran very well over 20 shots each tin.

cocks nice and easy , maybe a little bit lazy on firing ... going take it apart and look at the spring guide , just wondering now if its got hw77 internals like in a early forum post I read over the weekend.

just for reference how tight does the fit of the spring guide need to be when slipped into the spring , should the spring spin on the guide or should the whole lot spin on the block.

lastly re reducing the stroke , is it as simple as putting a tbt piston extension on to existing piston .

Thanks