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Spring Gun Tuning Gone Stagnant ?

Discussion in 'Technical' started by Nickg, Sep 23, 2021.

  1. Triggertime

    Triggertime Engaging Member

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    I don't think it has @Nickg it's just waiting for another break through of innovation maybe in the materials used? May be the whole design of the spring rifle needs a good look at? I'd say there is a few 'goldilocks' setups/tunes/ways of tuning/changing springers out there now (yours included!!) That are that good can people ask or want for more..I'd say how much further can they go?? May be compile a list of 'failings' or improvements things you would do away with or want from the rifles from you or any of the spring gun tuners that way any further advancement could be pin pointed and as so to narrow down and be worked on..I doubt its that simple but it could be a starting point?
     
    Last edited: Sep 23, 2021
    frenchy3 likes this.
  2. Commander M

    Commander M Engaging Member

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    Speaking from a "retired from design" design point of view. I think if you started with a clean sheet and only had to design up to a maximum of 11.5ft/lbs you could come up with something very special.

    As soon as you start thinking in terms of the higher power markets you're immediately bound by structural constraints. The tuners in the UK of today are bound by the over engineered (for potential higher power) mechanicals they have to work with. Really - how heavy duty does an 11.5ft HW97 need to be?
     
    vdubber likes this.
  3. FPoole

    FPoole Keyboard Hero

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    I shot a couple of different Theobens back in the day. Really sold me on metal coil springs.:D
     
    El Caro likes this.
  4. Chouchin66

    Chouchin66 Top Poster

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    Considering air can be classed as a fluid, perhaps a page from flow dynamics of water...a conical easement @ end of compression tube, to focus " flow forces" through the T.P. more efficiently. When building headwalls for drainage culverts, skew & flares are employed to create less eddy effect, reducing undercut & focusing the water to center of culvert... Though any gain in volume ( above spring line) must be calculated, & possibly a larger culvert used( T.P.) to keep good flow...just a thought

    .
     
    paj, DEGS and 1260engineer like this.
  5. DrGunn

    DrGunn Posting Addict

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    Isn’t this essentially what was tried with one of the early airsporters (mk2?)?
     
  6. 1260engineer

    1260engineer The Terminator's Armourer

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    yep thats called a BSA Airsporter :thumb:
     
  7. 1260engineer

    1260engineer The Terminator's Armourer

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    Mmmmm ...Apticote 2000 ceramic coated cylinder . multi stage piston . . and a few other gizmo's . wont say to much just in case i decide to build it . :D

    Ps. if anyone comes across a HW80 with a Nikasil coating in the cylinder. and 4 full length ceramic gliders on the piston .. . sunken faced trigger block that is adjustable. and has a variable TP port .
    guess what................ :D
     
    Chouchin66 likes this.
  8. frenchy3

    frenchy3 Engaging Member

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    Engineering design,technology and CAD design has come on in leaps and bounds in the last few years. New materials such as carbon fibre and high tech plastics too but what you have to consider is since the advent of PCP rifles which although look complex and expensive to produce are actually pretty cheap to manufacture. You can get a PCP that is almost recoiless,smooth and accurate to shoot,light weight etc etc. A spring powered gun is harder to achieve those results without the manufacturer having to market the rifle at a prohibitive cost which most potential buyers would baulk at. Of course really top end springers in a good state of tune could be made but where is the market for them these days. I know we are talking about the tuning business. I think spring piston and gas strut rifles being much heavier put people off as well. Try to lighten one of these too much and physics dictate that the perceived recoil increases. I love engineering and techy stuff and of course would like to see better technology and materials used in these rifles but bean counters dictate how much development a new rifle gets and what materials are used and manufacturing techniques applied in order to maximise profits. It always excites me though when new tuning ideas come out that improve how a rifle shoots and increases it,s accuracy but these minimal improvements may make a decent shot better but with me not so much:D:D
     
    paj likes this.
  9. TrickyDicky

    TrickyDicky Life in the slow lane

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    I have a friend who has designed and is in the process of building an opposing timed piston gun which has a rather unique cocking mechanism (not going into details) and in theory should be completely recoil less, i just hope he finishes it as it been in the pipeline for some years now.
     
  10. Bodge

    Bodge Engaging Member

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    Is jet pump technology something that could be incorporated into a spring rifle? Turning the transfer port into a Venturi somehow? Just a musing I had a while ago whilst procrastinating over doing the dog poo pick in the garden.
     
  11. Nickg

    Nickg Posting Addict

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    Coatings , in my target gun / test bed I have hard anodised ally comp tube with ptfe in the finish , piston sealed using a composite piston ring , the aim was low zero shift over a wide temp range which it achieves , the bonus is very low friction making extra power for the same amount of spring.
    Transfer ports, have tried everything including divergent convergent nozzle ( my brother is a gas turbine engineer) gains if any were minimal and not worth the hassle.Tgat diminishing returns thing again.☹️
     
    Bodge likes this.
  12. shergar

    shergar Big Poster

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    The fluid dynamics of water,(non compressible), and a gas,air,(compressible) differ to the extent that any comparison needs treating with caution. The boundary conditions for flow in open culvert also differs from that in a closed pipe.
     
  13. ajohn

    ajohn Chewing Things Over

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    What's really needed with spring guns is a gain in efficiency. Materials for the "body" aren't really that relevant. Some one claims to have done it
    https://www.airgunmagazine.co.uk/features/a-perfect-formula-airgun-design-breakthrough/

    Part of the problem is the nature of a spring. As it expands it exerts less pressure. ;) The solution to that is called a PCP.

    The transfer port is a woolly area. Going on one gun where I tapered it slightly and I do mean slightly it wrecked the firing cycle. Went from pretty smooth to rough so on this one it look like it is part of the tuning and used to change the piston's behaviour during it's stroke.
     
  14. shergar

    shergar Big Poster

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    In a spring air gun there is a double transfer of energy. First the spring transfers its energy to the air, then the air transfers energy to the pellet.
    Energy transfer air/pellet is dependant on loss in energy of the mass of air involved. Boyle's Law tells us that for a given mass of air, pressure and volume have an inverse relationship. The transfer port serves a double function. 1st to restrict flow in order to increase pressure in cylinder whilst simultaneously allowing through the greatest mass of air for energy transfer.
    An oversize TP will allow through a large volume of air but at low pressure. An undersize TP will create high pressure but restrict volume of air.
    A correctly sized TP optimises both pressure and volume to allow greatest mass of air to transfer power to pellet.
    In short putting through 1/2 the volume at twice the pressure transfers an equivalent mass, whilst a smaller piston can be lighter, require less spring and produces less recoil. Those at the forefront of these developments should be saluted for their achievements.
     
  15. ajohn

    ajohn Chewing Things Over

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    Due to the compressibility of air? Normally pressure in conventional hydraulics can be regarded as the same every where. The jet out of a garden hose pipe goes further as the nozzle size is reduced because the rate of the mass of water the same pressure is shifting is less.

    :facepalm: An over simplification of the differences. I neglected flow losses in the actual hose pipe and probably some other factors.

    On the other hand I still more see it's action as a method of controlling piston action and rate of movement. It's effectively controlling the rate pressure can build just as it does in a PCP. Springs on those are used to set timing / mass of air used.
     
  16. shergar

    shergar Big Poster

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    For water, volume & mass stay the same independent of pressure. A high pressure will push a greater volume of both water and air through a small hole but in the case of air it is compressed by the high pressure so mass/unit volume is also increased.
     
  17. td_boy

    td_boy Donator

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    Part of a springers appeal is it's simplicity - start using exotic alloys and adding complication and the selling price escalates out of proportion with the costs as the manufacturers see the opportunity to 'add value' :rolleyes:.

    The problem with that is they've already been pushing that angle with 'normal' spring guns like the HW 98 - now almost £500 for the standard version and the standard TX 200 hitting £600....

    With an HW 99 which is almost as good as either of the above costing just £250 and probably outselling them 100:1 - where is the market for a £1000+ springer?
     
    Neil Curtis and paj like this.
  18. wezil

    wezil Keyboard Hero

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    Yes all that tuning seems to do is take the rough edges of the factory gun where price is everything. And yes it can and does work, so big ups for those that can or do for the rest of us.
     
  19. Triggertime

    Triggertime Engaging Member

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    I'd buy a 1000 quid springer and I'm sure many others would especially if it had something special going on in its guts.. we are over half way there for a standard high quality springer out the box rifle now..then add on a tune and you are over 3/4 of the way there..pcp are almost the same tech as they where 30 years ago and cost 1000+ for a sporting rifle 2-3000 for a match rifle.. and no one coughs at that..and have you seen the price of venoms these days? And they have nothing in them that isn't being done/copied now besides them being legendary tuners and innovative in the time oh and some cost a 1000+ quid when new and people bought them...
     
  20. td_boy

    td_boy Donator

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    I don't think the market for a £1k+ mass market springer can be compared to the collectors market where reputation and rarity keeps prices high or to top-tier PCPs where people are prepared to buy competition success no matter what.

    So sure, they would probably sell a few hundred, but I can't see them selling in the volumes to make it worthwhile.

    I'm actually surprised one of the recognised tuners hasn't picked up the Venom baton as I do think there is a small well-heeled market for something beautifully stocked with something like a fluted barrelled Pro-sport type action.
    Some kind of collaboration with ISP perhaps?
     

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