HW97 puzzle opinion please

[deejayuu]

Excessive cocking effort especially last few mm to latch and set safety
Spring is 220 mm x 20.5 x 3 round 25 coils 42 lb/inch ME 11.5 with 7.9 gn
Internals 26 mm x 80 stroke
i) feels over sprung but removing spacers lowers output but no improvement
ii) latches easy in hand or assembled without spring
iii) seems better out of stock but no different in spare stock. No witness marks to wood
iv) not coil bound and no better without sleeve
v) guide/top hat not butting
vi) no better without ABT
vii) first stage not fouling stock
Ah! Just thought haven't tried without safety. See you've helped already

[charub]

Gym membership required?

[Phil Russell]

OK ... a puzzle.
Looking at it logically, I think you said that without the spring all was well with the cocking action? To me that indicates that somehow the spring is implicated.
I know you have tried without a spacer but have you tried without the top hat? As your issue seems to be over a couple of mm of cocking stroke (if I understand correctly) then this could translate to a very small movement in the cylinder area itself.
Have you made any changes to the internals? Was it fine previously but this has just happened?
Safety? Look forward to hearing the 'no safety' result as maybe, just maybe, a tab is catching.
Cheers, Phil

[joffy]

try it using another spring if you have one

[imorik]

As spring is compressed it expands outwards (O/D increases). Could be catching inside of piston ( or liner if you have fitted one). Another possibility is if latchrod is not central it may catch inside spring guide.

[Murphy]

Excessive is very subjective.

[CapitalBee]

Variation of spring i/d creating a tie up on the spring guide or top hat? Had this with a Walther Terrus spring; about 4 coils in the i/d was binding on the top hat.

[Phil Russell]

Not sure that variation in spring id is the answer ... the spring outer diameter would increase on compression, as would the id so I do not think the guide is an issue and as it is stated that the same thing happens with no liner, then the spring is not likely to be binding on compression. But stranger things have happened. This is why a little more info would be welcome ... is it a new 'to the rifle' spring? Has the issue just started? Has a strip just been done? Any trigger mods been made?
Cheers, Phil

[TonyL]

Many good suggestions up above and I'd certainly be trying it with a different spring. I was all on for also suggesting the spring OD expansion, but as it's no better when removing the sleeve........

Also worth pursuing Imorik's idea on the latch rod.

[deejayuu]

Many thanks all. Quick response hoping I don't miss anyone.
Arrived needing ME reducing. Cocking smooth but excessive effort compared to same model/spec and sears blocking unless lever jerked at latch point.
Stripping revealed issues i) floating cocking lever rivet ii) damaged male threads to stock lug iii) buckled trigger interlock
iv) main/intermediate sear fouling casing tang ( blocking culprit?) v) bent trigger blade pivot vi) indent on first sear from trigger blade inserts ( often due to triggering out of block with no main sear stop pin)
Guide is two part steel brazed together very neatly. Liner is very well made steel. Synthetic top hat. Spring does not appear to be factory item.
Top hat was removed with no effect. Latch rod is well through guide/block before problem occurs and doesn't bind when no spring fitted
Just obtained HW spring so will update on that. Hope responses to this thread is of use to others. Dim but willing. Jules

[deejayuu]

HW spring fitted and great improvement in cocking effort/latching action. 11.5 ft.lb. with 7.9 gn Express
Quite satisfied with that. Thanks for the support.

[joffy]

HW spring fitted and great improvement in cocking effort/latching action. 11.5 ft.lb. with 7.9 gn Express
Quite satisfied with that. Thanks for the support.

Nice when that happens

[TonyL]

Nice one.