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The safety lever assembly in the low power shot position. Note the flats on the shaft that have now slid into view after emerging from the left hand side of the grip handle.
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The above hydropneumatic gun is by Valentin. Below is a pneumatic version using the same stylistic principles. Not a mass production gun, unlike the Girstitan being discussed here. The pull rod running under the tank indicates a forward latching weapon.
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Perhaps you could give these guns their own thread as not much point in showing them here.
Pete, how is the sliding rubber cuff sealed to the releasing valve body? Has the biasing spring some role in that?This diagram shows how water injected during muzzle loading squeezes past the rubber cuff on the releasing valve by pushing it back on its biasing spring while the releasing valve body remains locked in place by the trigger mechanism.
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The hydrostatic pressure when the gun is charged forces the rubber cuff against the metal disc and its connecting cylindrical shank that forms the front of the releasing valve body. You could compare the rubber cuff to the sealing flange of a plug in a sink outlet, but here it seals a thin ring around the metal head of the plug and the rear face of the inner barrel. Because the annular gap created is small the hydrostatic pressure cannot force the rim of the rubber cuff through the gap. That gap has ambient pressure in the inner barrel on one side and charged to shoot pressure on the other side created by the annular piston transferring air pressure from the tank to the water trapped in the rear of the gun. The biasing spring helps to return the rubber cuff, but the hydrostatic pressure is what really seals it as any water flow is cut off before it can escape through that small gap.Pete, how is the sliding rubber cuff sealed to the releasing valve body? Has the biasing spring some role in that?
Yes, I thought it was like what you explained.The hydrostatic pressure when the gun is charged forces the rubber cuff against the metal disc and its connecting cylindrical shank that forms the front of the releasing valve body. You could compare the rubber cuff to the sealing flange of a plug in a sink outlet, but here it seals a thin ring around the metal head of the plug and the rear face of the inner barrel. Because the annular gap created is small the hydrostatic pressure cannot force the rim of the rubber cuff through the gap. That gap has ambient pressure in the inner barrel on one side and charged to shoot pressure on the other side created by the annular piston transferring air pressure from the tank to the water trapped in the rear of the gun. The biasing spring helps to return the rubber cuff, but the hydrostatic pressure is what really seals it as any water flow is cut off before it can escape through that small gap.
Note for these releasing valves to work the diameter of the rear bore that the releasing valve's body "O" ring is located in is always larger than the bore of the inner barrel.
Yes, I thought it was like what you explained.
It is similar in working principle to one of my early ideas presented on this forum some years ago, but this is for hydro pneumatic supergun and has more simpler design and is actually proved in exploitation. My remained just as an idea..
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The tapered shank design was used on the later Aquatech guns which had brass tails on their spears. The drilled port earlier tails are less likely for the "O" ring to be peeled off with the shaft skidding along the bottom, in fact they are difficult to slide by hand to open or shut.you can also do this