Results 1 to 6 of 6

Thread: The Daystate electronic air rifles de-mystified | Review

  1. #1
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default The Daystate electronic air rifles de-mystified | Review

    Daystate's Air Wolf, Grand Prix and Mk4 rifles all incorporate electronics.





    When I first heard about them all I knew was that they work with batteries and that they emit beeping sounds, I was at the time still busy satisfying my curiosity about the Blizzard, Anschutz, S200, S510 and HW100's workings.

    One came up for sale and we bought it for Linda after she saw one of our worlds competitors in action with his GP, it's a GP FAC we got her.

    Few months later and we now have three of them, two FACs and one dedicated 12fpe GP. Me being a staunch purist did not view the electronic newcomer favourably at first, on hindsight; it was simply because I did not know how and why it worked. I must admit, as a professional photographer I also at first did not think digital electronics had a place in photography, my colour and b&w darkrooms were soon donated to a school and a powerful PC replaced a darkened room full of equipment and poisonous chemicals almost overnight, doubling my productivity and creativity. (= More time to play with air rifles )

    Soon after having a closer look the GP I realised that the electronics involved was no more intricate than what's found in automated gate openers. Don't get me wrong, the way old technology and electronic principles were integrated and applied to Daystate's PCP's is brilliant, what I'm saying is that there's no mysterious vulnerable unproven secret microchips, principles or other components involved here, only robust long proven generally used components and electronic principles put to brilliant use.
    Once I realised this I felt no more intimidated or unsure about the reliability or workings of the GP's than a S200, in fact I was so enlightened and amazed by the simplicity that I'm also now eyeing the MK4 Walnut stock Daystate.



    What's different compared to a conventional PCP?

    The energy and duration with which the hammer strikes the firing valve is precision electronically controlled.

    How? The hammer is the core of a solenoid, a device so long in use that it made the first telephone ring. Momentum is provided by the electro-magnetic field generated by the coil of the solenoid and not a conventional coiled hammer spring.
    We rolled electrical wire around a thin tube as kids and were able to shoot needles from the tube by connecting the device to a battery. In this case the hammer is the needle.

    How does it know how much energy is needed for the hammer to strike the valve with predictable outcome?
    It's got a chronograph built into the barrel shroud extension to tell the micro processor what velocity the pellet is doing. It also has an electronic pressure gauge which feeds info to the micro processor to calculate the energy needed for the coil to propel the hammer with predictable outcome.



    In short this is what happens when the trigger is activated:

    The trigger being a high quality micro switch release an instantaneous exact amount of electricity stored in an electrolytic capacitor to magnetise the solenoid coil. This value was calculated by an algorithm programmed into the micro processor which use data recorded from the previous shot and knowledge of the opposing air pressure on the other side of the valve.

    Electrolytic capacitors are basically reservoirs which can be filled by a feeble current until full and then they can release a lot of energy in a very short and precisely calculated time, like a large sluice opened. This sudden surge of electricity is applied to the coil of the solenoid which excels the hammer which in turn hits the firing valve releasing a measured pulse of compressed air to accelerate the pellet down the barrel.



    This concept is known as Capacitive Discharge Technology, CDT, and was brought to airgun design by Stephen Harper and David Snook in the eighties. Electronic camera flashes had been using the concept since early seventies, regulated capacitor discharge results in perfect exposure by a xenon filled glass tube and output is calculated by measuring elapsed time of light returning from the photographed subject.

    This process was dubbed Mapped Velocity Technology, MVT by Daystate. In the electronic models without chronograph the rifle operates according to pre-set values and it is called Map Compensated Technology, MCT.

    Advantages over mechanical devices:

    Superior lock time due to an electronic triggering system used, five times faster compared to a sluggish chain of mechanical events to release the air. It takes a mere 5 milliseconds from trigger activation for the hammer to strike the valve fully open. By the time this happens a mechanical hammer would still be on its way to the valve.
    The Daystate hammer is centered on its travel forward by a magnetic field, it does not even touch the inside of the solenoid coil, no mechanical wear is present which eliminates lubricants, a major cause of velocity inconsistency.

    Another bonus to the use of electro magnetism to move the hammer opposed to a mechanical coiled spring is the lack of hammer bounce, resulting in very economical air consumption since the lack of wasted air and unnecessary turbulence behind the pellet affecting accuracy negatively.
    A spring driven hammer can bounce back from the valve into the spring and gets thrown forward again resulting in another pulse of air released from the valve after the pellet started down the barrel.
    When the micro processor of an electronic Daystate cuts the current to the coil the hammer force stops instantaneously. There's a weak spring only to return the hammer to it's starting position.
    This obviously also makes a hammer spring cocking device unnecessary, the bolt is only used to seat the pellet. Air efficiency is phenomenal, I get 150 shots at 12fpe from a 205 bar fill. (The rifle counts the shots for me and a beep tells me it's down to 55bar and going off regulation. A glance at the chrony reading will confirm this.)



    Because the trigger is simply a micro switch it beats any competition trigger hands down for sensitivity, no creep, no polishing of sears needed, imagine clicking a computer mouse with adjustable spring load, that's almost as smooth as it feels.

    The processor knows exactly what pressure it's dealing with and at which speed the given pellet travels. Extreme spread is only dictated by the quality of pellets used.

    The energy can be user dictated, you can tell it what velocity you want it to shoot your favourite pellet at.
    The FAC GP's will shoot a 8.4gn pellet at 500fps up to 1010fps depending on what you set it at. (What gets most fiddled with on air rifles? Power output and consistency = hammer springs, regulators, the cumbersome fiddling to balance the two components, if not by yourself then by some "Guru" to whom the rifle gets shipped, man, do the courier companies love this!) With Daystate's MVT technology it's done PRECICELY with the push of a button, right there where you're sitting shooting, no spanners involved! I rest my case.



    Some obvious questions:

    How long does the battery last on a charge?
    Very long, the circuitry is very power efficient. 5 tins of pellets between charges is not uncommon, if you live without access to electricity to charge the rifle you can even resort to a small 9 volt alkaline battery to power the rifle. It will turn itself off if not fired in 10 mins in case you forget to switch it off before torage. The battery itself also is no rocket component, it's made up of 8 normal AA penlight NiMh 1.2v cells (available on battery shelves in most shops) connected in series and shrink wrapped into a pack.

    How do you know it needs charging?
    The GP shows the voltage level on the display screen. The batteries can be topped up after every shoot without adverse effect being nickel metal hydride batteries.

    How do you know the MVT rifle performs at the velocity set by you?
    It displays the exact velocity of every shot.

    What if you get caught in the rain with an electronic rifle?
    The electronic circuit boards are coated with a water repellent varnish
    and Daystate had a rifle in a tank at their IWA 2004 exhibit already which was sprayed with water for four days and it still worked.

    How does the rifle know when you change to a different weight pellet?
    It will realise it the moment the velocity deviates from the previous shot fired, it will then use the next two shots to calculate and adjust it's power to shoot the new pellet weight at the speed you chose.

    It will also do the same if you change the velocity setting or refill the cylinder. It is intelligent enough however to realise you forgot to put a pellet into the breech when the chrony returns a zero value, it will not adjust immediately but will fire the next shot at the same speed as the last pellet, same goes for an extreme velocity deviation like shooting a cleaning pellet at 1500fps, it will wait for the next shot to see if it needs to adjust, if you keep shooting cleaning pellets it will adjust power to shoot them at
    the speed you set the rifle at.

    Does it need 3 shots after every switch on to do it's calculations?
    No, if nothing changed i.e. pellet weight or cylinder pressure it will simply continue shooting as it was before switch off. Some very early models would need 3 shots after every switch off to get up to set velocity again, this has been improved by Daystate long ago.

    What maintenance is needed?
    None other than perhaps replacing the rechargeable battery pack after about 5 years and routine barrel cleaning which include cleaning of the chrony "eyes" in the shroud tip with a mascara brush like the girls use to apply mascara to their eye lashes.

    The electronic circuits are of modular surface mount design so defective modules can easily and time effectively be unplugged and swapped out if needed. There's a chronograph, main board and display driver module, LCD display, pressure sensor, solenoid coil and a battery pack.

    The crony is safely tucked away on the outside of the air stripper tube which sits in the barrel shroud extension, only four tiny holes provide access to the pellet path for the two infra red beams to measure pellet speed.
    Unlike chronies with sky screens no external light is needed for the chrony to function. The air stripper tube is held in place by a threaded end cap on the shroud. No lead dust builds up on the chrony "eyes", I checked a GP with at least 3000 shots through it and could not find any lead dust on the IR Led's, cleaning pellets might be a culprit but I'll explain the solution to that further down.

    Firmware updating is possible by the local agent in case Daystate makes a drastic change to the way the micro processor thinks. The one FAC can be set to warn when the pressure in the cylinder drops to a pre-set value, the other FAC cannot, but both display the pressure left on the LCD. The unfortunate reason for Daystate not making it possible for the user to simply download and update the firmware himself like camera and GPS firmware I guess is the FAC restrictions in Britain. It would be possible to illegally upgrade a 12fpe rifle to a FAC spec then.

    The micro processor is also put to other good uses besides regulating the pellet speed, it displays voltage, pellet speed and bar left, it can also display shot count and charging status while the charger is plugged in, it even has a magazine count reminder for the models using magazines.



    User input is accomplished by using the trigger when held down at switch on, the rifle then enters the menu mode and it can be set to user preference. The models without displays use audible signals for programming and communicating with the user.

    What's next?
    There's not much to be improved on the principle or the consistency of these electronic rifles, so all that's left to change would be to add nice to haves.
    I guess we might see the integration of a memory card to log and record shot strings and other shooting data downloadable to computer. Once this already generally used technology is incorporated, firmware updates could be effected by simply loading it onto the memory card and inserting it into the rifle. Data encoding linked with embedded rifle serial numbers can be used to avoid illegal upgrading.
    It could be taken further, user preferences could be stored on the card and the rifle could respond to a specific user's card. No, that would mean I might have to share my GP, let's skip that idea! A stopwatch function would be more useful.
    Trigger release could perhaps be achieved by breaking an infra red beam, either by mechanical device or finger, the latter would enable a bench shooter to fire the rifle without touching a trigger! Bench rules might have to be rewritten. Must admit though, bench rules do accommodate electronic triggers as they are. Jean Michel Jarre made music on an electronic organ by using fingers to break beams more tan 10 years ago already.

    I cannot wait to see which manufacturer will be first to take the bold step to follow in Daystate's footsteps and adopt electronics in their rifles. All I know is that they will be years (decades?) behind Daystate who will remain the undisputed pioneers of electronic air rifle design.

    Accuracy? These rifles are common at Nationals and Worlds, 'nuff said.

    Some notes on the GP as such:

    If you or anybody else for some reason (most likely to service the chrony) remove the barrel and top part of the action, take GREAT care when replacing it not to pinch the 3 core flex wire running to the chrony from the action. I have encountered two previously worked on GP's with pinched wires. The wire is routed between the barrel shroud and the cylinder in a perfect fit channel and through the action to the main board in an even
    more perfect fitting machined channel. If it's not put back with greatest care two things happen: The barrel does not float above the cylinder as intended resulting in POI shift. Worse, the very thin conductor breaks inside the insulation resulting in a frustrating intermittent chrony malfunction with temperature or pressure change. This can only be
    determined by using a continuity tester while manhandling the wire to see if it's broken inside the insulation.

    If you have a GP and plan to use cleaning pellets, de-burr the chrony "eye" holes in the air stripper, the burrs on these tiny holes catch the fibres of the expanded felt pellet when it passes and the chrony beam is blocked resulting in a 0fps chrony reading. In this case the rifle will default to maximum power, still fully regulated and consistent, 20fpe in the case of the FAC and 12fpe in the non FAC version until the problem is rectified with mascara brush.

    Last, don't EVER fire the rifle with the shroud end cap off, you will shoot the chrony and air stripper out the shroud extension resulting in a broken chrony wire. Encountered one such case, can happen.



    Hopefully after reading all this you will also realise that the electronic Daystates are simply PCP's with the massive advantage of using proven electronic technology to achieve extreme consistency and accuracy. It's WAY less of a mystery than an entry level point and shoot digital camera's workings, desktop calculator or even electronic engine management on a scooter. You keep the battery charged, it keeps on shooting.

    Discussion at: https://www.airrifle.co.za/threads/38781
    Sign Up To Air Rifle SA Forums

  2. #2
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default

    CHRONY UPDATE
    Here's some insight on the mysterious chrony in the barrel shroud tip of the MVT rifles, this one a GP.
    I have had some questions regarding cleaning the chrony 'eyes', some claim a cotton wad helps, here's why it won't;
    The problem is not the lead dust in the air stripper tube, it's the dust build up on the sensor 'eyes' located in the tiny holes in the air stripper.
    On this photo one of the tiny holes is clearly visible, also the burr I spoke about in the original post can clearly be seen:

    The IR LED's and photo transistors have tiny protrusions that clips into the holes in the air stripper to create light barriers across the pellet path.


    Here the assembled chrony and air stripper can be seen. The chrony pc board is mounted on the outside of the air stripper with components out of harm's way. Only way to damage the board is to shoot the chrony out the shroud when forgetting to screw the end plug on before shooting. The chrony connecting wire can't give so the connector gets ripped out the socket and damages the surface mount components in it's way.

    The nice thing is that they used an opto Schmitt beam trigger, this basically means the chrony will not gradually give false readings as the light path gets blocked by lead dust, it will either totally work or not at all. Unlike a light dependent resistor the opto Schmitt needs an exact amount of light cut-off else it will not function and typically the chrony will display 0fps.

    0Fps is when you know you should already have cleaned the sensors.

    I'm in the process of making a dedicated brush to get deep enough into those small holes to wipe the sensors clean. I want to make some markings on the brush stem so you know exactly when the brush is at the right depth into the air stripper to be lined up with the chrony eye holes.

    Will post pics when I've made the brush. In the meantime we are using a mascara brush as found at cosmetic counters.
    Sign Up To Air Rifle SA Forums

  3. #3
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default

    A quick update here.
    NOTE ON CHARGERS:

    Mark your Daystate charger, with all the rechargeable consumer electronics around chances are that the wrong charger/power supply might end up with the wrong gadget. I have noted complaints of 'charger problems' that might be contributed to mix ups.

    I have at least 3 power supplies that could be confused with Daystate chargers, one for a cordless drill, one for a portable powerpack and another for a desktop printer.

    The new generation Daystate chargers actually has "Daystate" printed on the spec tag, but in SUPER small font. It should be a 15volt 0.4amp switch mode supply. The female jack on the charger must be 5.5mm outside diameter and 2mm inside diameter with positive connected to the inside of the female and negative outside.

    Happy shooting.
    Sign Up To Air Rifle SA Forums

  4. #4
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default

    Just a quick update with more info:

    The latest Daystate charger for identification purposes in case you mixed it up with the rechargeable drill charger :


    Electronic trigger adjustment in case you bought a rifle who's previous owner used the manual to start his braai fire with:


    The Daystate manuals are available for download from Daystate here:
    http://www.daystate.com/handbooks.htm
    Sign Up To Air Rifle SA Forums

  5. #5
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default

    And one more thing I'd like to add on behalf of all future used electronic Daystate buyers; If you are selling a used electronic Daystate and you have thought yourself brilliant enough to have fiddled with/tried in vain to have tuned/bettered anything on Daystate's original design, be honest and bold enough to inform the buyer that you have STUFFED IT UP.

    The electronic Daystate rifles perform best as is OUT THE BOX, there's nothing to be TUNED on them, I know I have said that repeatedly over the years. I still stick to that observation. I have not seen a single IMPROVEMENT on the original design, I have seen LOTS of excellent rifles stuffed up by 'tuning', sadly everytime AFTER they've been sold on to an unsuspecting buyer.

    The aim of this thread is to inform and explain how these rifles work and every rifle I have worked on until now was to fix things that owners or ex owners broke trying to 'tune' these rifles.

    My Wolf MVT I was fortunate enough to buy out the box 3 years ago has not missed a beat, Linda's MVT Wolf the same, her GP AFTER we fixed it (bought second hand stuffed up by a tuner owner) 4 years ago has not missed a beat since fixed.

    Keep 'em charged, filled with air and clean and enjoy shooting the most technologically advanced air rifles in the world. Start 'tuning' and be prepared to sell it on to an unsuspecting buyer or have stupidly-stuffed-up parts replaced at great cost.

    ////rant off///
    Sign Up To Air Rifle SA Forums

  6. #6
    Sharp Shooter
    ARF Member Of The Year 2011

    User Info Menu

    Default

    So another crippled Airwolf MVT found its way to the work table. This specific one was sold by "you know whom" ex Daystate "agent" on this forum a while back to Bex as a 'new' rifle 'specially built for 100m competitions by Daystate'. Laugh My Arse Off, thanking you kindly

    Let me just make it clear, me and Linda are not airgun smiths, nor are we Daystate specialists, we only happen to have bought many crippled MVT's in the past and were forced to find our way around the workings in order to fix what previous owners and "agents" broke by fiddling and or "tuning". A lot of times the fiddling only manifests itself as a total breakdown many shots later. Lead powder build-up causes short circuits on damaged components, components are damaged during fiddling. So MZE asked us to sort his newly aquired Wolf which had a chrony playing up.

    Stripping down revealed the typical tell tale signs of the 'engineer's' handiwork, the pinched chrony cable. This one was not only squashed by the rifle's action, it was squashed on a kink. A quick continuity test revealed two exposed conductors on the kink, recipe for intermittent short circuit with ambient temperature change:


    HWY???, because someone removed the breech from the action and did not take note of the way Daystate route this very thin 3 core flex wire.

    Then, this tinkerer thought it wise to route the chrony wire OVER the highest component on the chrony board as to ensure wear and tear of the little wire against the inside of the shroud. Brilliant man, you produced a time lapsed malfunction, the insulation gave way and lead dust build up caused an expected short after a few thousand shots rendering the Wolf MVT a "bad electronic rifle" with "chronies always break".
    The second pic shows the way Daystate intended the routing to be like, note the o-rings are not meant to raise the wire for wear and tear:



    The circuit boards are inspected under a stereo microscope for damage. Multimeter does not work to check since the boards are varnished to repel water and to resist lead build-up short circuits. It only takes a slip of a screwdriver to damage the board, and you won't even realise it until you check with a microscope. (Still thinking of 'tuning' it while it's working perfectly?)



    Linda meticiously cleaned the barrel. It had lead build-up to the extent where the typical rust layer is sealed in by lead. 30 pull throughs later she got through the rust layer to reveal the actual clean barrel grooves again.



    I hear what you "never clean barrel" shooters say but personally, having shot a variety of Daystates, I believe maximum accuracy and consistency is achieved with clean barrels on these rifles.

    Rifle re-assembled, chrony wire insulation fixed with varnish and damaged varnish on circuit boards touched up. 130 test shots fired without chrony malfunction. Doing 50 more after the rifle was left in the sun for 20 mins.

    Hopefully we managed to restore this rifle to before-fiddling Daystate factory specs. If so MZE will have many many years of care free service from this rifle.

    Discussion at: https://www.airrifle.co.za/threads/38781
    Sign Up To Air Rifle SA Forums


Similar Threads

  1. Daystate Mk4 diy electronic board
    By jhnntfts in forum DIY Workbench
    Replies: 20
    Last Post: 28-02-19, 21:26
  2. The Daystate electronic air rifles de-mystified
    By DvdM in forum Airgun Discussions
    Replies: 85
    Last Post: 25-10-14, 00:27
  3. Daystate Air Wolf MCT 5.5mm - Review part 1/2
    By horvath brother in forum Airgun Discussions
    Replies: 0
    Last Post: 03-07-12, 20:49
  4. Falcon Air Rifles | Review
    By Yeti in forum Airgun Reviews
    Replies: 4
    Last Post: 13-06-11, 19:00
  5. daystate air rifles........
    By urabus in forum Airgun Discussions
    Replies: 4
    Last Post: 23-11-05, 14:37

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Friends of Air Rifle SA