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Oil for use in pneumatic spearguns

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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
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Australia
My father could not dive deeper than 12 meters and I never hunted with that gun. 95% of hunted fish was mullet in 4 meters of water. And usually when they hunt Tuna the depth is 300-3000! he got lucky to get that gun back!
Yes, just as well not over the Marianas Trench!
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Speaking of not so wimpy hand pumps here is a high pressure pump from China which appears to be a clone of the Swedish FX high pressure pumps that use 3 concentric pumping tubes to reach 3000 psi. A lot cheaper in terms of price, but their durability is unknown, however may be OK for pressurizing a "Black Sea" and other high pressure hydropneumatic guns as they require about 100 bar or 1,500 psi. The innermost pump barrel in a thin rod pushing into a close fitting bore which makes such high pressures possible, albeit with a lot of pump strokes and using all your body weight on the pump handle.

This is the patent diagram for the FX pump and was no doubt eagerly read by the engineers at SMACO!
FX High Pressure hand pump patent.jpg
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
The Chinese economy is built on it, although they can generate their own improvements and then devote any R&D to building on the work already done by others. They are selling these high pressure pumps for about one third to a quarter of the price of the Swedish FX pumps and partly that is due to the latter's distributors selling to a captive market that has no other options. For example I looked at buying a FX pump here from the only distributor who was based at some remote rural location in the middle of nowhere. The FX pump was going to cost me more than a gun and all the usual accessories, so I passed up on it.

Shipping from the USA where there were more FX hand pump sellers was very expensive and was not an option. In fact US shipping is generally expensive as it is from Italy making shipping the major cost component for some items.
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
I ordered and received one of these SMACO hand pumps which was delivered today. All up cost was 120 bucks including shipping and taxes. In the package you receive a bunch of white plug type disposable filters which I guess are to take care of the filtering requirements for breathable air, however I have no intention of using it for air cylinders as I wanted it to pump up my hydropneumatic guns. They use start pressures 80 bar and up to about 110 bar (small diameter inner barrels) and it should be much easier using a hand pump designed for 200 bar. You still do the same amount of work, but with much fewer pump strokes because these pumps use 3 stage compression and are two-way acting. The usual hand pumps supplied with pneumatic guns are usually good to 40 bar, but a lot depends on the dead space with the pump connected to the gun as the pump stroke swept volume divided by the dead space volume determines the pump's maximum compression ratio.
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
This is the operating leaflet that comes with the pump. Very tiny writing, but hopefully it is legible.
SMACO High Pressure Pump A.jpg
SMACO High Pressure Pump B.jpg

This was slightly crushed inside the package, but I put it under a heavy book for a week to flatten it out, still has a few creases in it which show up on a scan.
 
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