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Thread: HW99s imp / No Top Hat

  1. #1
    Join Date
    May 2008
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    HW99s imp / No Top Hat

    Hi guys.

    I have a question please regarding my 3 year old SFS HW99s imp. And my question Is, why doesn't the imp come fitted with a top hat? I only know this because I remember hearing Tony Wall giving this info to a customer at SFS when I collected the rifle from his shop.

    And because I'm not handy with airguns or Indeed never actually stripped a springer down myself, I'm a bit confused. Why, because even I know that a spring air rifle needs a guide and a top hat to keep the spring stable during the firing cycle. So If that's the case, why hasn't the imp got a top hat fitted? My imp Is a joy to shoot, the cocking cycle Is as smooth as silk, the recoil Is minimal and the accuracy Is superb. But how can this be the case without a top hat? Why fit a top hat to any air rifle If such good results can be achieved without one?

    Any info on this query guys will be greatly appreciated
    God created man and god created woman
    Sam colt made them equal

  2. #2
    Join Date
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    Mmmmmm.......like yourself, really not sure about this one. After all, any well-presented and refined gentlemanly spring seems underdressed to me without a top hat.

    Are you sure that Tony wasn't pulling this other chap's todger?
    THE BOINGER BASH AT QUIGLEY HOLLOW. MAKING GREAT MEMORIES SINCE 15th JUNE, 2013.
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  3. #3
    Join Date
    Apr 2007
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    Top Hat

    Some of my early venom's don't have a top hat as they weren't about back then. With the right spring set up you don't need one. The 35 Vixen produce in 1978 doesn't use a top hat and shoots lovely. Mach 1.5
    Last edited by Mach 1.5; 27-02-2022 at 01:40 PM.

  4. #4
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    If the piston bore clearance between that and the outside diameter of the spring has been taken up with a correctly sized sleeve - what good does a top hat do anyway?

  5. #5
    Garry's Avatar
    Garry is offline I scrolled the page up too fast and it fell off
    Join Date
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    I thought a top hat was there as a form of bearing for the end of the spring. That's the impression I have from what's inside my TX HC. It's the only rifle I've ever had, so probably wrong in that assumption.

  6. #6
    Join Date
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    If the Imp is so good, why worry? It is perfectly normal to add a slip washer between the end of the spring and the bottom of the piston. A top hat can keep the spring central to the piston but if the fit is good anyway, most likely helped by a piston sleeve then it is dubious if a top hat will add anything extra .. but I have come across quite firmly fitted top hats that have a slip washer on them. Note that you don't want a top hat to be a very tight fit in the piston and a very tight fit in the spring such that it restricts the spring from 'unwinding' as it expands during a shot.
    Cheers, Phil

  7. #7
    Join Date
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    two main functions.

    1) centralise spring in piston. May not be needed if the spring OD is a tight fit in the piston ID, but there has to be some slack to allow for compression, so it'll not be 100%
    2) front brearing for spring to rotate against (with a slip washer)

    also two secondary functions
    3) secure piston sleave in place
    4) ensure spring is seated squarely on the inside face of the piston

    I really think every gun should have one.
    Always looking for any cheap, interesting, knackered "project" guns. Thanks, JB.

  8. #8
    Join Date
    May 2008
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    973
    Thanks for the replies and Info guys
    God created man and god created woman
    Sam colt made them equal

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