Reg creep?

Discussion in 'General Airgun Chat' started by Gibbs, Oct 17, 2011.

  1. Gibbs

    Gibbs New Member

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    Three comp's in a row, I have missed the first target of the course. All three went low.
    Is this a sign of reg creep in my Steyr?
    And if so, can I assume it would show up on the chrono as quite a large drop in velocity?

    Atb,

    Alec.
     
  2. Knockedover

    Knockedover CSFTA Champ

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    Is the gun quick fill or removable cylinder? Do you fire any shots off after refilling?
    Both of my removable cylinder steyrs, and others I've had experience of, need a shot through them after a refill to get them back to spot on, I'm sure it takes the first shot to get the reg refilled correctly to get them back on song. I have noticed that quick fill guns don't tend to drop the first shot as the reg is kept up to pressure:)
     
  3. Gibbs

    Gibbs New Member

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    My Steyr has the removable cylinder and I have been aware of the lower shots after a fill for a long time. I always fill before a comp and then always go on the zero range to settle it in. This first lower shot seems to be after the gun has been sitting around for a while. I havent fired off any shots just before I shoot the first lane, as I didn't think there was any need.
    Also, is it good to dry fire? Doesn't it "slamdunk" the reg? would it be better to fire a pellet into the ground instead?

    Atb,

    Alec.
     
  4. TonyF

    TonyF SWEFTA FT Champion 2006

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    Alec

    I ALWAYS fire one or two at the very first lane. I thought that I had advised you to do the same and then you won't miss the first shot low! ;)
     
  5. wiseguy

    wiseguy Active Member

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    if your reg is leaking, the pressure in the valve chamber will be more than the normal value, sometimes near the pressure of the cylinder. The hammer isn't able to open the valve far and long enough due to this over pressure, resulting in a big velocity drop. You may notice a lower poi.
    This can be easily measured with a crony.
    So if you suspect your regulator to be faulty, this is a possible scenario and way to diagnose.
    regards,
    Rob
     
  6. Gibbs

    Gibbs New Member

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    Thank's for the replies,
    I haven't seen any drop through the chrono in the past and I have tested it with a time delay. Maybe the delay wasn't long enough.
    I guess I will have to add the wasted shot/s to my routine.
    Atb,

    Alec.
     
  7. Tench

    Tench WHFTA World Champion 2016.

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    It is not definitely the reg, a slight leak from the firing valve can cause a low first shot if the gun has stood a while, or a small rise in pressure within the reg due to it not sealing could cause a rise in the first shot, a larger pressure rise within the reg is needed to produce a low first shot. Either way it is always a good idea to fire a couple off to cycle the reg and get everything back into its stride, putting a pellet into the ground with the last of your pre shots is also a good idea as when dry firing the cooling expanding air can leave moisture behind which can result in a wet bore which could produce a high first shot due to better pellet seal and the moisture acting as a lube. i have experience high first shots several times even when the reg has been cycled, but never since i started to put one in the ground to dry the bore.
     
  8. RobF

    RobF Administrator Staff Member

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    do it against a dialed in known target Alec when you test, else if you rangefind, you add the possibility that you could just misrange your first target.
     
  9. NJR 100

    NJR 100 Because I`m AWESIME !!

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    its 5 minutes on an Ev2 alex.

    could try the same time period for styer?

    Fire over chrono, wait 5mins, then if first shot is 20 or more fps below average, you haver a perfectly normal Ev2!:D
     
  10. Gibbs

    Gibbs New Member

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    Thank's for the replies,
    I have waited over 5 minutes before and found no problem with the poi at 55 yards so maybe it's a new problem?
    It's not under ranging as I have checked with my shooting partners after their shot and also shot some of the targets after the comp.
    I will need to simulate comp timing of filling and zero check and then see how many shots I need to fire off before my first target.
    If my S400 had a match trigger! I would be thinking about making a Steyr style FT stock for it!
    It didn't suffer any of this prima donna stuff.

    Atb,

    Alec.
     

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